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Not supported with pagination yet | Select the phase of the Moon shown in the model. | [
"first quarter",
"new"
] | 1 | The model below shows the Moon at one position in its orbit around Earth. The white half of the Moon shows the part that is lit up by the Sun. | closed choice | grade5 | natural science | earth-science | Astronomy | Identify phases of the Moon | Although the Moon appears to shine, it does not give off light. Instead, we can see the Moon because it is lit up by the Sun. The part of the Moon that is both lit up by the Sun and facing Earth is called the Moon's phase.
The Moon orbits, or goes around, Earth. As it does, the Moon's phase changes. The model below shows the Moon's phase at eight positions in its orbit. The smaller moons closer to Earth show where sunlight hits the Moon. The larger moons farther from Earth show how the Moon will look during that phase.
To use the model, first pick one of the eight positions. Then, imagine standing on Earth and looking up at the Moon. Use the dotted white lines in the model to guide you. The picture of the Moon shows its phase for that position. If you are in the Southern Hemisphere, the Moon will appear flipped, left to right. | |
What is the capital of Indiana? | [
"Norfolk",
"Columbus",
"Topeka",
"Indianapolis"
] | 3 | closed choice | grade5 | social science | geography | State capitals | Identify state capitals of the Midwest | Indianapolis is the capital of Indiana. |
|||
Based on the arrows, which of the following living things is a decomposer? | [
"kelp",
"bat star"
] | 1 | Below is a food web from an ocean ecosystem. The ecosystem is in Monterey Bay, off the coast of California.
A food web is a model that shows how the matter eaten by living things moves through an ecosystem. The arrows show how matter moves through the food web. | closed choice | grade3 | natural science | biology | Ecosystems | Interpret food webs | A food web is a model.
Models can make things in nature easier to understand. Models can be simpler than the things they represent. A food web is a model that shows where living things in an ecosystem get their food. If a food web showed every living thing in an ecosystem, the food web would be hard to understand. So, each food web shows how some living things in an ecosystem can get their food.
Arrows show how matter moves.
A food web has arrows that point from one living thing to another. Each arrow shows the direction that matter moves when one living thing eats another living thing. An arrow starts from the living thing that is eaten. The arrow points to the living thing that is doing the eating.
A living thing in a food web can have more than one arrow pointing from it. This shows that the living thing is eaten by more than one other living thing in the food web.
A living thing in a food web can also have more than one arrow pointing to it. This shows that the living thing eats more than one other living thing in the food web. | Decomposers help break down dead living things into simpler matter, such as nutrients. These nutrients can then help plants and other living things grow. In a food web, there is an arrow pointing from another living thing to a decomposer. There are no arrows pointing from a decomposer to another living thing.
The kelp has an arrow pointing from it. So, the kelp is not a decomposer.
The bat star does not have arrows pointing from it to other living things. So, the bat star is a decomposer. |
|
Not supported with pagination yet | Which figure of speech is used in this text?
Would you please be careful with my new laptop? That thing cost a million dollars! | [
"euphemism",
"hyperbole"
] | 1 | closed choice | grade9 | language science | figurative-language | Literary devices | Classify figures of speech: euphemism, hyperbole, oxymoron, paradox | Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive.
A euphemism is a polite or indirect expression that is used to de-emphasize an unpleasant topic.
The head of Human Resources would never refer to firing people, only to laying them off.
Hyperbole is an obvious exaggeration that is not meant to be taken literally.
I ate so much that I think I might explode!
An oxymoron is a joining of two seemingly contradictory terms.
Some reviewers are calling this book a new classic.
A paradox is a statement that might at first appear to be contradictory, but that may in fact contain some truth.
Always expect the unexpected. | The text uses hyperbole, an obvious exaggeration that is not meant to be taken literally.
A million dollars is an exaggeration, since it is unlikely that a laptop would actually cost a million dollars. |
|
Not supported with pagination yet | Which figure of speech is used in this text?
Love is an ideal thing, marriage a real thing.
—Johann Wolfgang von Goethe | [
"assonance",
"antithesis"
] | 1 | closed choice | grade11 | language science | figurative-language | Literary devices | Classify the figure of speech: anaphora, antithesis, apostrophe, assonance, chiasmus, understatement | Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive.
Anaphora is the repetition of the same word or words at the beginning of several phrases or clauses.
We are united. We are powerful. We are winners.
Antithesis involves contrasting opposing ideas within a parallel grammatical structure.
I want to help, not to hurt.
Apostrophe is a direct address to an absent person or a nonhuman entity.
Oh, little bird, what makes you sing so beautifully?
Assonance is the repetition of a vowel sound in a series of nearby words.
Try to light the fire.
Chiasmus is an expression in which the second half parallels the first but reverses the order of words.
Never let a fool kiss you or a kiss fool you.
Understatement involves deliberately representing something as less serious or important than it really is.
As you know, it can get a little cold in the Antarctic. | The text uses antithesis, the contrasting of opposing ideas within a parallel grammatical structure.
Goethe contrasts love, an ideal thing, with marriage, a real thing. |
|
Select the bird below. | [
"cane toad",
"ostrich"
] | 1 | Birds have feathers, two wings, and a beak. A robin is an example of a bird. | closed choice | grade3 | natural science | biology | Classification | Identify mammals, birds, fish, reptiles, and amphibians | Birds, mammals, fish, reptiles, and amphibians are groups of animals. The animals in each group have traits in common.
Scientists sort animals into groups based on traits they have in common. This process is called classification. | An ostrich is a bird. It has feathers, two wings, and a beak.
The ostrich is the largest bird alive today. Ostriches cannot fly, but they can run very fast.
A cane toad is an amphibian. It has moist skin and begins its life in water.
Toads do not have teeth! They swallow their food whole. |
|
Not supported with pagination yet | Does this passage describe the weather or the climate?
It is snowing in Sam's town today. | [
"climate",
"weather"
] | 1 | Hint: Weather is what the atmosphere is like at a certain place and time. Climate is the pattern of weather in a certain place. | closed choice | grade3 | natural science | earth-science | Weather and climate | What's the difference between weather and climate? | The atmosphere is the layer of air that surrounds Earth. Both weather and climate tell you about the atmosphere.
Weather is what the atmosphere is like at a certain place and time. Weather can change quickly. For example, the temperature outside your house might get higher throughout the day.
Climate is the pattern of weather in a certain place. For example, summer temperatures in New York are usually higher than winter temperatures. | Read the text carefully.
It is snowing in Sam's town today.
This passage tells you about the precipitation today in Sam's town. It describes the atmosphere at a certain place and time. So, this passage describes the weather. |
Not supported with pagination yet | Complete the sentence so that it uses personification.
The ancient oak tree () under the weight of its own branches. | [
"cracked",
"slouched"
] | 1 | closed choice | grade10 | language science | writing-strategies | Creative techniques | Use personification | Personification is giving human characteristics to nonhuman things. It is a figure of speech that can be used to make writing more interesting or to emphasize a point.
The trees danced in the wind.
The word danced describes the trees as if they were people. Unlike people, however, trees can't actually dance. Instead, the personification suggests that the trees are moving. | Complete the sentence with the word slouched. It describes the tree as if it were a person with slumping shoulders. |
|
What is the direction of this pull? | [
"toward her hand",
"away from her hand"
] | 0 | A student opens her desk drawer. She uses a force to pull out the drawer. | closed choice | grade4 | natural science | physics | Force and motion | Identify directions of forces | A force is a push or a pull that one object applies to another. Every force has a direction.
The direction of a push is away from the object that is pushing.
The direction of a pull is toward the object that is pulling. | The student pulls open her desk drawer. The direction of the pull is toward her hand. |
|
Not supported with pagination yet | Which change best matches the sentence?
A glacier scrapes pieces of rock off a mountain and carries them downhill. | [
"landslide",
"drought",
"erosion"
] | 2 | closed choice | grade3 | natural science | earth-science | Earth events | Classify changes to Earth's surface II | |||
During this time, thermal energy was transferred from () to (). | [
"each refrigerator . . . the surroundings",
"the surroundings . . . each refrigerator"
] | 1 | Two identical refrigerators in a restaurant kitchen lost power. The door of one fridge was slightly open, and the door of the other fridge was closed. This table shows how the temperature of each refrigerator changed over 10minutes. | closed choice | grade7 | natural science | physics | Thermal energy | Compare thermal energy transfers | A change in an object's temperature indicates a change in the object's thermal energy:
An increase in temperature shows that the object's thermal energy increased. So, thermal energy was transferred into the object from its surroundings.
A decrease in temperature shows that the object's thermal energy decreased. So, thermal energy was transferred out of the object to its surroundings. | The temperature of each refrigerator increased, which means that the thermal energy of each refrigerator increased. So, thermal energy was transferred from the surroundings to each refrigerator. |
|
Which country is highlighted? | [
"Kiribati",
"Nauru",
"the Marshall Islands",
"Solomon Islands"
] | 2 | closed choice | grade7 | social science | geography | Oceania: geography | Identify and select countries of Oceania | This country is the Marshall Islands.
Does the Marshall Islands have any territorial disputes?
The Marshall Islands claims to own Wake Island, which is a disputed territory. In other words, multiple countries or groups claim that the area rightfully belongs to them.
The United States claimed Wake Island in 1899 and has controlled it since then. But the Marshall Islands considers the island part of its territory. It says that its people have traveled to the island to gather food and resources for many years. Today, the island is mainly used by the U.S. Air Force. |
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Not supported with pagination yet | Which sentence is more formal? | [
"The student council requested that more lockers be installed ASAP to accommodate the incoming freshman class.",
"The student council requested that more lockers be installed immediately to accommodate the incoming freshman class."
] | 1 | closed choice | grade5 | language science | writing-strategies | Author's purpose and tone | Which sentence is more formal? | Formal writing is used for essays, business letters, and reports. The following types of informal language should be avoided in formal writing:
Type | Examples
slang | cool, awesome
idioms | knock your socks off
conversational language | gonna, kinda, yeah
abbreviated language | ASAP, FYI
overly simple or imprecise language | he got some stuff at the store
contractions | can't, won't
Contractions are not as informal as the other types, but they should be used sparingly in formal writing.
Compare the following sentences. The first is informal. The second is formal.
Informal: Yeah, ostriches can't fly, but they're awesome runners.
Formal: Though ostriches are flightless, they are remarkably adept runners.
| The first sentence is less formal. You can tell because it uses abbreviated language (ASAP).
The second sentence does not use abbreviated language, so it is more formal. |
|
Not supported with pagination yet | How long is a tennis racket? | [
"26 yards",
"26 inches",
"26 feet",
"26 miles"
] | 1 | Select the best estimate. | closed choice | grade7 | natural science | units-and-measurement | Units and measurement | Choose customary units of distance, mass, and volume | Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means.
When you are using customary units, length may be written with units of inches, feet, yards, or miles.
There are 12 inches in 1 foot, and 3 feet in 1 yard. There are 5,280 feet in 1 mile.
A football is about 1 foot long. A football field is 100 yards long. | The best estimate for the length of a tennis racket is 26 inches.
26 feet, 26 yards, and 26 miles are all too long. |
Not supported with pagination yet | Which is smoother? | [
"plastic bucket",
"burlap sack"
] | 0 | closed choice | grade2 | natural science | physics | Materials | Compare properties of materials | Every object is made of one or more materials. A material is a type of matter. Wood, glass, metal, and plastic are common materials.
A material has different properties. A material's properties tell you how it looks, feels, tastes, or smells. | Smooth is a property. A smooth material is not rough or bumpy.
Look at each picture, one at a time. Imagine touching the material shown in each picture.
Of the choices, the plastic bucket is smoother. If you touch a plastic bucket like this one, it will not feel rough. |
|
Not supported with pagination yet | Select the vertebrate. | [
"snowy owl",
"peacock butterfly",
"bess beetle",
"Caribbean spiny lobster"
] | 0 | Hint: Mammals, birds, fish, reptiles, and amphibians are vertebrates. | closed choice | grade5 | natural science | biology | Classification | Identify vertebrates and invertebrates | Vertebrates and invertebrates are both groups of animals.
A vertebrate has a backbone. The backbone is made of many bones in an animal's back. A vertebrate's backbone helps connect the different parts of its body. In the drawings below, each vertebrate's backbone is colored orange.
An invertebrate does not have a backbone. In fact, invertebrates do not have any bones! Some invertebrates have an outer cover on their body called an exoskeleton. Other invertebrates have a soft body. | A bess beetle is an insect. Like other insects, a bess beetle is an invertebrate. It does not have a backbone. It has an exoskeleton.
A Caribbean spiny lobster is a crustacean. Like other crustaceans, a Caribbean spiny lobster is an invertebrate. It does not have a backbone. It has an exoskeleton.
A snowy owl is a bird. Like other birds, a snowy owl is a vertebrate. It has a backbone.
A peacock butterfly is an insect. Like other insects, a peacock butterfly is an invertebrate. It does not have a backbone. It has an exoskeleton. |
Not supported with pagination yet | Which logical fallacy is used in the text?
If the government is allowed to start blocking websites, then soon they'll start banning books, and all we'll have to read is propaganda. | [
"slippery slope fallacy: the false assumption that a small first step will lead to extreme consequences",
"appeal to nature: the assumption that natural things are always good",
"circular reasoning: an argument that supports a claim with the claim itself"
] | 0 | closed choice | grade12 | language science | writing-strategies | Developing and supporting arguments | Classify logical fallacies | A strong argument uses valid reasoning and logic in support of a claim. When an argument or claim introduces irrelevant information or misrepresents the issues at hand, it may be committing a logical fallacy. Logical fallacies can hurt a writer's credibility and can lead readers to draw false conclusions.
A logical fallacy may present irrelevant information:
Fallacy | Description
ad hominem | an attack against the person making the argument, rather than the argument itself
appeal to nature | an argument that assumes the natural choice is always the best choice
bandwagon fallacy | an argument that assumes the popular choice is always the best choice
circular reasoning | an argument that supports a claim with the claim itself
guilt by association | an unfair negative association with another person or group that is intended to discredit someone or something
A logical fallacy may misrepresent the issues at hand:
Fallacy | Description
false causation | the assumption that because two things happened together, one caused the other
false dichotomy | an argument that presents only two choices when more options exist
hasty generalization | a broad claim based on too few observations
slippery slope fallacy | the false assumption that a small first step will necessarily lead to extreme consequences
straw man | a misrepresentation of an opponent's position that makes it easier to argue against
| The text argues that blocking websites will eventually lead to having only propaganda to read. However, this isn't necessarily true. This argument offers only one extreme and unlikely outcome. This illustrates a type of logical fallacy known as the slippery slope fallacy. |
|
Not supported with pagination yet | Which object has the most thermal energy? | [
"a 150-gram glass of orange juice at a temperature of 26°C",
"a 150-gram glass of orange juice at a temperature of 7°C",
"a 150-gram glass of orange juice at a temperature of 6°C"
] | 0 | The objects are identical except for their temperatures. | closed choice | grade4 | natural science | physics | Heat and thermal energy | How is temperature related to thermal energy? | All solids, liquids, and gases are made of matter. Matter is made up of tiny particles that are always moving. The energy from the motion of these particles is called thermal energy.
Temperature measures how hot or cold matter is. If the particles in matter move faster, the temperature goes up. The matter now has both more thermal energy and a higher temperature. | All three glasses of orange juice have the same mass but different temperatures. Since the 26°C glass of orange juice is the hottest, it has the most thermal energy. |
Is the wind through a tree a solid, a liquid, or a gas? | [
"a solid",
"a gas",
"a liquid"
] | 1 | closed choice | grade4 | natural science | physics | States of matter | Identify and sort solids, liquids, and gases | Solid, liquid, and gas are states of matter. Matter is anything that takes up space. Matter can come in different states, or forms.
When matter is a solid, it has a definite volume and a definite shape. So, a solid has a size and shape of its own.
Some solids can be easily folded, bent, or broken. A piece of paper is a solid. Also, some solids are very small. A grain of sand is a solid.
When matter is a liquid, it has a definite volume but not a definite shape. So, a liquid has a size of its own, but it does not have a shape of its own. Think about pouring juice from a bottle into a cup. The juice still takes up the same amount of space, but it takes the shape of the bottle.
Some liquids are thicker than others. Honey and milk are both liquids. But pouring honey takes more time than pouring milk.
When matter is a gas, it does not have a definite volume or a definite shape. A gas expands, or gets bigger, until it completely fills a space. A gas can also get smaller if it is squeezed into a smaller space.
Many gases are invisible. The oxygen you breathe is a gas. The helium in a balloon is also a gas. | Wind through a tree is air that is moving! Air is a gas. The air expands to fill the space around each tree branch. |
||
Not supported with pagination yet | Is the following trait inherited or acquired?
Anna has naturally red hair. | [
"acquired",
"inherited"
] | 1 | Hint: Some people dye their hair. But this does not change their natural hair color. | closed choice | grade4 | natural science | biology | Traits and heredity | Identify inherited and acquired traits | Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways.
Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned.
Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Children do not inherit their parents' acquired traits. | Humans do not choose their natural hair color. Instead, children get their natural hair color from their parents. So, Anna's hair color is an inherited trait. |
Which country is highlighted? | [
"New Zealand",
"Palau",
"the Marshall Islands",
"Papua New Guinea"
] | 0 | closed choice | grade6 | social science | geography | Oceania: geography | Identify and select countries of Oceania | This country is New Zealand. |
|||
What is the name of the colony shown? | [
"North Carolina",
"Rhode Island",
"Delaware",
"Georgia"
] | 3 | closed choice | grade8 | social science | us-history | Colonial America | Identify the Thirteen Colonies | The colony is Georgia. |
|||
Not supported with pagination yet | Select the animal. | [
"Hydrangea bushes can grow colorful flowers.",
"Sea otters eat animals that live in the ocean."
] | 1 | closed choice | grade2 | natural science | biology | Classification | Identify plants and animals | Plants and animals are living things. Living things are called organisms.
Plants come in many shapes and sizes. Most plants grow in the ground. They might grow leaves, flowers, and fruit. Plants cannot move around on their own like animals can.
Animals also come in many shapes and sizes. Most animals can move around. Animals might run, swim, jump, or fly. Animals eat plants or other organisms for food. | A sea otter is an animal. It eats animals that live in the ocean.
Sea otters have very thick fur. Their fur keeps them warm in cold water.
A hydrangea bush is a plant. It can grow colorful flowers.
Hydrangea bushes can have blue, white, purple, or pink flowers. |
|
Which ocean is highlighted? | [
"the Atlantic Ocean",
"the Indian Ocean",
"the Southern Ocean",
"the Pacific Ocean"
] | 3 | closed choice | grade6 | social science | geography | Physical Geography | Oceans and continents | Oceans are huge bodies of salt water. The world has five oceans. All of the oceans are connected, making one world ocean. | This is the Pacific Ocean. |
||
Which animal's mouth is also adapted to eat plant matter? | [
"cougar",
"impala"
] | 1 | Goats are herbivores, or plant eaters. They eat grass and leaves. The 's mouth is adapted to grind up and eat plant matter.
Figure: goat. | closed choice | grade4 | natural science | biology | Adaptations | Animal adaptations: beaks, mouths, and necks | An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors.
The shape of an animal's mouth is one example of an adaptation. Animals' mouths can be adapted in different ways. For example, a large mouth with sharp teeth might help an animal tear through meat. A long, thin mouth might help an animal catch insects that live in holes. Animals that eat similar food often have similar mouths. | Look at the picture of the goat.
The goat has long jaws and flat teeth. Its mouth is adapted to eat plant matter. The long jaws can help the goat reach leaves and grass. The flat teeth can help it cut and grind up the food into soft pieces it can swallow.
Now look at each animal. Figure out which animal has a similar adaptation.
The impala has long jaws and flat teeth. Its mouth is adapted to eat plant matter.
The cougar has a large mouth and sharp teeth. Its mouth is not adapted to eat plant matter. The cougar uses its mouth to eat other animals. |
|
Not supported with pagination yet | Suppose Destiny decides to take a trip to Virginia. Which result would be a cost? | [
"Destiny will enjoy her trip to Virginia more than she would have enjoyed a trip to Connecticut.",
"Destiny will spend more money. Plane tickets for Destiny to get to Virginia are more expensive than tickets to Connecticut."
] | 1 | Destiny is deciding whether to take a trip to Virginia or Connecticut. She wants to enjoy her trip. But she is also trying to save money. | closed choice | grade5 | social science | economics | Basic economic principles | Costs and benefits | Before you decide to do something, it is often helpful to list costs and benefits.
Costs are what you give up or spend when you decide to do something. Costs involve giving up things that you want or need.
Benefits are what you gain or save when you decide to do something. Benefits involve gaining something that you want or need. | This result is a cost. It involves giving up or spending something that Destiny wants or needs:
Destiny will spend more money. Plane tickets for Destiny to get to Virginia are more expensive than tickets to Connecticut. |
Not supported with pagination yet | Based on this information, what is Rover's phenotype for the fur length trait? | [
"ff",
"long fur"
] | 1 | In a group of dogs, some individuals have short fur and others have long fur. In this group, the gene for the fur length trait has two alleles. The allele F is for short fur, and the allele f is for long fur.
Rover, a dog from this group, has long fur. Rover has two alleles for long fur. | closed choice | grade8 | natural science | biology | Genes to traits | Genetics vocabulary: genotype and phenotype | All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different alleles, or forms, that can cause different versions of a trait.
For example, flower color is a trait in pea plants. The gene for this trait has two possible alleles. Each allele is represented by an uppercase or lowercase letter. The allele F is for purple flowers, and the allele f is for white flowers. Each pea plant has two alleles for the flower color gene—one allele inherited from each parent.
An organism's genotype for a gene is its combination of alleles for that gene. So, a pea plant may have a genotype of FF, Ff, or ff for the flower color gene.
An organism's phenotype for a trait is its observable version of that trait, which depends on the organism's combination of alleles. A pea plant may have a phenotype of purple flowers or white flowers for the flower color trait. | An organism's phenotype for a trait is its observable version of that trait. Rover's observable version of the fur length trait is long fur. So, Rover's phenotype for the fur length trait is long fur. |
Complete the text to describe the diagram.
Solute particles moved in both directions across the permeable membrane. But more solute particles moved across the membrane (). When there was an equal concentration on both sides, the particles reached equilibrium. | [
"to the left than to the right",
"to the right than to the left"
] | 0 | The diagram below shows a solution with one solute. Each solute particle is represented by a purple ball. The solution fills a closed container that is divided in half by a membrane. The membrane, represented by a dotted line, is permeable to the solute particles.
The diagram shows how the solution can change over time during the process of diffusion. | closed choice | grade6 | natural science | chemistry | Solutions | Diffusion across membranes | In a solution, solute particles move and spread throughout the solvent. The diagram below shows how a solution can change over time. Solute particles move from the area where they are at a higher concentration to the area where they are at a lower concentration. This movement happens through the process of diffusion.
As a result of diffusion, the concentration of solute particles becomes equal throughout the solution. When this happens, the solute particles reach equilibrium. At equilibrium, the solute particles do not stop moving. But their concentration throughout the solution stays the same.
Membranes, or thin boundaries, can divide solutions into parts. A membrane is permeable to a solute when particles of the solute can pass through gaps in the membrane. In this case, solute particles can move freely across the membrane from one side to the other.
So, for the solute particles to reach equilibrium, more particles will move across a permeable membrane from the side with a higher concentration of solute particles to the side with a lower concentration. At equilibrium, the concentration on both sides of the membrane is equal. | Look at the diagram again. It shows you how the solution changed during the process of diffusion.
Before the solute particles reached equilibrium, there were 4 solute particles on the left side of the membrane and 6 solute particles on the right side of the membrane.
When the solute particles reached equilibrium, there were 5 solute particles on each side of the membrane. There was 1 more solute particle on the left side of the membrane than before.
So, for the solute particles to reach equilibrium, more solute particles must have moved across the membrane to the left than to the right. |
|
Think about the magnetic force between the magnets in each pair. Which of the following statements is true? | [
"The magnitude of the magnetic force is the same in both pairs.",
"The magnitude of the magnetic force is greater in Pair 2.",
"The magnitude of the magnetic force is greater in Pair 1."
] | 1 | The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material. | closed choice | grade7 | natural science | physics | Velocity, acceleration, and forces | Compare magnitudes of magnetic forces | Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces.
The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other.
You can change the magnitude of a magnetic force between two magnets by changing the distance between them. The magnitude of the magnetic force is greater when there is a smaller distance between the magnets. | The magnets in Pair 2 attract. The magnets in Pair 1 repel. But whether the magnets attract or repel affects only the direction of the magnetic force. It does not affect the magnitude of the magnetic force.
Distance affects the magnitude of the magnetic force. When there is a smaller distance between magnets, the magnitude of the magnetic force between them is greater.
There is a smaller distance between the magnets in Pair 2 than in Pair 1. So, the magnitude of the magnetic force is greater in Pair 2 than in Pair 1. |
|
Not supported with pagination yet | How long is a kitchen table? | [
"7 yards",
"7 inches",
"7 feet",
"7 miles"
] | 2 | Select the best estimate. | closed choice | grade7 | natural science | units-and-measurement | Units and measurement | Choose customary units of distance, mass, and volume | Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means.
When you are using customary units, length may be written with units of inches, feet, yards, or miles.
There are 12 inches in 1 foot, and 3 feet in 1 yard. There are 5,280 feet in 1 mile.
A football is about 1 foot long. A football field is 100 yards long. | The best estimate for the length of a kitchen table is 7 feet.
7 inches is too short. 7 yards and 7 miles are too long. |
Not supported with pagination yet | What is the source of the allusion in the sentence below?
Red velvet cupcakes were Deb's Achilles's heel when she was trying to eat more healthily. | [
"Greek mythology",
"the Bible"
] | 0 | closed choice | grade10 | language science | figurative-language | Literary devices | Recall the source of an allusion | An allusion is a brief mention of something or someone well known, often from mythology, history, or literature. An allusion lets you reference ideas from an entire story in just a few words.
"I'd better get home before I turn into a pumpkin!" Lila remarked.
Here, Lila alludes to the fairy tale "Cinderella," in which Cinderella must leave the ball before the coach that brought her transforms into a pumpkin. The allusion shows that Lila must depart immediately. | The source of the allusion Achilles's heel is Greek mythology.
In Greek mythology, Achilles's mother dips him in a river that protects his body wherever it touches. His heel does not get wet, so it is the one part of his body left unprotected. During the Trojan War, an arrow hits Achilles in the heel and kills him.
The allusion Achilles's heel means a sole weakness. |
|
Not supported with pagination yet | Which word would you find on a dictionary page with the following guide words?
dine - drown | [
"dozen",
"design"
] | 0 | closed choice | grade2 | language science | reference-skills | Reference skills | Use guide words | Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order.
To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on. | Put the words in alphabetical order.
Since dozen is between the guide words dine - drown, it would be found on that page. |
|
Select the chemical formula for this molecule. | [
"BF3",
"BFe3",
"HB3F",
"B2F3"
] | 0 | closed choice | grade5 | natural science | chemistry | Atoms and molecules | Match chemical formulas to ball-and-stick models | Every substance around you is made up of atoms. Atoms can link together to form molecules. The links between atoms in a molecule are called chemical bonds. Different molecules are made up of different chemical elements, or types of atoms, bonded together.
Scientists use both ball-and-stick models and chemical formulas to represent molecules.
A ball-and-stick model of a molecule is shown below.
The balls represent atoms. The sticks represent the chemical bonds between the atoms.
Notice how each ball is labeled with a symbol made of one or more letters. The symbol is an abbreviation for a chemical element. The ball represents one atom of that element.
Every chemical element is represented by its own symbol. For some elements, that symbol is one capital letter. For other elements, it is one capital letter followed by one lowercase letter. For example, the symbol for the element boron is B and the symbol for the element chlorine is Cl.
The molecule shown above has one boron atom and three chlorine atoms. A chemical bond links each chlorine atom to the boron atom.
The chemical formula for a molecule contains the symbol for each chemical element in the molecule. Many chemical formulas use subscripts. A subscript is text that is smaller and placed lower than the normal line of text.
In chemical formulas, the subscripts are numbers. The subscript is always written after the symbol for an element. The subscript tells you how many atoms that symbol represents. If the symbol represents just one atom, then no subscript is included.
The symbols in the chemical formula for a molecule match the symbols in the ball-and-stick model for that molecule. The ball-and-stick model shown before and the chemical formula shown above represent the same substance. | B is the symbol for boron. F is the symbol for fluorine. This ball-and-stick model shows a molecule with one boron atom and three fluorine atoms.
The chemical formula will contain the symbols B and F. There is one boron atom, so B will not have a subscript. There are three fluorine atoms, so F will have a subscript of 3.
The correct formula is BF3.
The diagram below shows how each part of the chemical formula matches with each part of the model above. |
||
Not supported with pagination yet | Which greeting is correct for a letter? | [
"Dear Uncle Jim,",
"dear Uncle Jim,"
] | 0 | closed choice | grade4 | language science | punctuation | Formatting | Greetings and closings of letters | A letter starts with a greeting and ends with a closing. For each one, capitalize the first word and end with a comma. You should also capitalize proper nouns, such as Aunt Sue.
Dear Aunt Sue,
I'm glad you could come to my party, and
thank you for the birthday gift. I could not have
asked for a better one! Every time I see it, I think
of you.
With love,
Rory | The first greeting is correct:
Its first word is capitalized, and it ends with a comma. Uncle Jim is capitalized because it is a proper noun. |
|
Not supported with pagination yet | According to the passage, which statement is true? | [
"The Congress of the United States makes laws.",
"Congress does not have legislative power."
] | 0 | The Legislative Branch is described in Article I of the United States Constitution. Read Section 1 of Article I. Then answer the question.
All legislative powers herein granted shall be vested in a Congress of the United States, which shall consist of a Senate and House of Representatives.
legislative: law-making
vested in: given to
consist: be made up of | closed choice | grade8 | social science | civics | Government | The Legislative Branch | ||
Is scoria a mineral or a rock? | [
"rock",
"mineral"
] | 0 | Scoria has the following properties:
no fixed crystal structure
has many small holes
not a pure substance
found in nature
solid
not made by organisms | closed choice | grade8 | natural science | earth-science | Rocks and minerals | Identify rocks and minerals | Minerals are the building blocks of rocks. A rock can be made of one or more minerals.
Minerals and rocks have the following properties:
Property | Mineral | Rock
It is a solid. | Yes | Yes
It is formed in nature. | Yes | Yes
It is not made by organisms. | Yes | Yes
It is a pure substance. | Yes | No
It has a fixed crystal structure. | Yes | No
You can use these properties to tell whether a substance is a mineral, a rock, or neither.
Look closely at the last three properties:
Minerals and rocks are not made by organisms.
Organisms make their own body parts. For example, snails and clams make their shells. Because they are made by organisms, body parts cannot be minerals or rocks.
Humans are organisms too. So, substances that humans make by hand or in factories are not minerals or rocks.
A mineral is a pure substance, but a rock is not.
A pure substance is made of only one type of matter. Minerals are pure substances, but rocks are not. Instead, all rocks are mixtures.
A mineral has a fixed crystal structure, but a rock does not.
The crystal structure of a substance tells you how the atoms or molecules in the substance are arranged. Different types of minerals have different crystal structures, but all minerals have a fixed crystal structure. This means that the atoms and molecules in different pieces of the same type of mineral are always arranged the same way.
However, rocks do not have a fixed crystal structure. So, the arrangement of atoms or molecules in different pieces of the same type of rock may be different! | The properties of scoria match the properties of a rock. So, scoria is a rock. |
|
Not supported with pagination yet | Is there a sentence fragment?
In 2004, a team of archaeologists discovered a three-foot-tall skeleton, dubbed the "Hobbit," in Indonesia. Even after ten years, experts still debate whether the skeleton belonged to a modern human. | [
"yes",
"no"
] | 1 | yes or no | grade12 | language science | writing-strategies | Sentences, fragments, and run-ons | Identify sentence fragments | A sentence is a group of words that expresses a complete thought.
The band I'm in has been rehearsing daily because we have a concert in two weeks.
A sentence fragment is a group of words that does not express a complete thought.
Rehearsing daily because we have a concert in two weeks.
This fragment is missing a subject. It doesn't tell who is rehearsing.
The band I'm in.
This fragment is missing a verb. It doesn't tell what the band I'm in is doing.
Because we have a concert in two weeks.
This fragment is missing an independent clause. It doesn't tell what happened because of the concert. | There is not a sentence fragment. These are complete sentences because they express complete thoughts.
In 2004, a team of archaeologists discovered a three-foot-tall skeleton, dubbed the "Hobbit," in Indonesia. Even after ten years, experts still debate whether the skeleton belonged to a modern human. |
|
Not supported with pagination yet | Which of the following contains a vague pronoun reference? | [
"Hares are often mistaken for rabbits, even though their legs, feet, and ears are usually bigger.",
"Hares are often mistaken for rabbits, even though hares' legs, feet, and ears are usually bigger."
] | 0 | closed choice | grade7 | language science | writing-strategies | Pronouns and antecedents | Identify vague pronoun references | When writing, make sure to avoid vague pronoun references. A vague pronoun reference occurs when a pronoun could refer to more than one possible antecedent.
When Lisa and Kim finally landed, she breathed a sigh of relief.
The pronoun she could refer to either Lisa or Kim, so the meaning of the sentence is unclear.
Vague pronoun references can be corrected in one of two ways:
1. Replace the pronoun with its correct antecedent:
When Lisa and Kim finally landed, Lisa breathed a sigh of relief.
2. Rewrite the sentence:
Lisa breathed a sigh of relief when she and Kim finally landed.
A vague pronoun reference also occurs when they, them, their, theirs, it, or its is used without its antecedent.
They say that this nail polish dries in less than five minutes.
The pronoun they is used without its antecedent, so the meaning of the sentence is unclear.
This problem can be fixed by replacing the pronoun with its missing antecedent.
The advertisements say that this nail polish dries in less than five minutes. | The second answer choice contains a vague pronoun reference. The pronoun their could refer to hares' or rabbits'.
The first answer choice shows a possible correction for the vague pronoun reference. Their has been replaced with hares'.
Hares are often mistaken for rabbits, even though hares' legs, feet, and ears are usually bigger. |
|
What is the capital of Illinois? | [
"Louisville",
"Springfield",
"Phoenix",
"Chicago"
] | 1 | closed choice | grade3 | social science | geography | State capitals | Identify state capitals of the Midwest | Springfield is the capital of Illinois. |
|||
Not supported with pagination yet | How long is a car? | [
"4 miles",
"4 feet",
"4 inches",
"4 yards"
] | 3 | Select the best estimate. | closed choice | grade7 | natural science | units-and-measurement | Units and measurement | Choose customary units of distance, mass, and volume | Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means.
When you are using customary units, length may be written with units of inches, feet, yards, or miles.
There are 12 inches in 1 foot, and 3 feet in 1 yard. There are 5,280 feet in 1 mile.
A football is about 1 foot long. A football field is 100 yards long. | The best estimate for the length of a car is 4 yards.
4 inches and 4 feet are too short. 4 miles is too long. |
Which property do these three objects have in common? | [
"translucent",
"opaque",
"fragile"
] | 1 | Select the best answer. | closed choice | grade3 | natural science | physics | Materials | Compare properties of objects | An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it.
Different objects can have properties in common. You can use these properties to put objects into groups. | Look at each object.
For each object, decide if it has that property.
A translucent object lets light through. But you cannot see clearly through a translucent object. None of the objects are translucent.
A fragile object will break into pieces if you drop it. None of the objects are fragile.
An opaque object does not let light through. All three objects are opaque.
The property that all three objects have in common is opaque. |
|
What is the capital of Washington? | [
"Spokane",
"Seattle",
"Jefferson City",
"Olympia"
] | 3 | closed choice | grade5 | social science | geography | State capitals | Identify state capitals of the West | Olympia is the capital of Washington. |
|||
Which i in column 3? | [
"the library",
"the restaurant",
"the police department",
"the grocery store"
] | 3 | closed choice | grade3 | social science | geography | Geography | Use a letter-number grid | A grid is made up of lines of squares. They are organized in rows and columns. A grid can help you use a map.
A row is a line of squares that goes from side to side. Rows are marked with letters.
A column is a line of squares that goes up and down. Columns are marked with numbers. | The grocery store is in column 3. |
||
Not supported with pagination yet | What is the source of the allusion in the sentence below?
Myra thinks Mr. Harper is a Luddite because he doesn't own a cell phone. | [
"British history",
"Roman history"
] | 0 | closed choice | grade9 | language science | figurative-language | Literary devices | Recall the source of an allusion | An allusion is a brief mention of something or someone well known, often from mythology, history, or literature. An allusion lets you reference ideas from an entire story in just a few words.
"I'd better get home before I turn into a pumpkin!" Lila remarked.
Here, Lila alludes to the fairy tale "Cinderella," in which Cinderella must leave the ball before the coach that brought her transforms into a pumpkin. The allusion shows that Lila must depart immediately. | The source of the allusion Luddite is British history.
In the early nineteenth century, factories were replacing the jobs of craftsmen. Some of these craftsmen banded together to destroy the new machinery; those who did so were called Luddites.
The allusion Luddite means a person opposed to new technology. |
|
Does this passage describe the weather or the climate? | [
"climate",
"weather"
] | 0 | Figure: Blue Nile Falls.
Blue Nile Falls is in Ethiopia. The winds in this part of Africa usually blow from the southeast.
Hint: Weather is what the atmosphere is like at a certain place and time. Climate is the pattern of weather in a certain place. | closed choice | grade4 | natural science | earth-science | Weather and climate | Weather and climate around the world | The atmosphere is the layer of air that surrounds Earth. Both weather and climate tell you about the atmosphere.
Weather is what the atmosphere is like at a certain place and time. Weather can change quickly. For example, the temperature outside your house might get higher throughout the day.
Climate is the pattern of weather in a certain place. For example, summer temperatures in New York are usually higher than winter temperatures. | Read the passage carefully.
Blue Nile Falls is in Ethiopia. The winds in this part of Africa usually blow from the southeast.
The underlined part of the passage tells you about the usual wind patterns at Blue Nile Falls. This passage does not describe what the weather is like on a particular day. So, this passage describes the climate. |
|
Which property do these three objects have in common? | [
"translucent",
"opaque",
"fragile"
] | 1 | Select the best answer. | closed choice | grade3 | natural science | physics | Materials | Compare properties of objects | An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it.
Different objects can have properties in common. You can use these properties to put objects into groups. | Look at each object.
For each object, decide if it has that property.
A translucent object lets light through. But you cannot see clearly through a translucent object. None of the objects are translucent.
A fragile object will break into pieces if you drop it. None of the objects are fragile.
An opaque object does not let light through. All three objects are opaque.
The property that all three objects have in common is opaque. |
|
Not supported with pagination yet | Based on this information, what is Pudge's genotype for the body color gene? | [
"Bb",
"a gray body"
] | 0 | In a group of guppies, some individuals have a gray body and others have a golden body. In this group, the gene for the body color trait has two alleles. The allele B is for a gray body, and the allele b is for a golden body.
Pudge, a guppy from this group, has a gray body. Pudge has one allele for a gray body and one allele for a golden body. | closed choice | grade7 | natural science | biology | Genes to traits | Genetics vocabulary: genotype and phenotype | All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different alleles, or forms, that can cause different versions of a trait.
For example, flower color is a trait in pea plants. The gene for this trait has two possible alleles. Each allele is represented by an uppercase or lowercase letter. The allele F is for purple flowers, and the allele f is for white flowers. Each pea plant has two alleles for the flower color gene—one allele inherited from each parent.
An organism's genotype for a gene is its combination of alleles for that gene. So, a pea plant may have a genotype of FF, Ff, or ff for the flower color gene.
An organism's phenotype for a trait is its observable version of that trait, which depends on the organism's combination of alleles. A pea plant may have a phenotype of purple flowers or white flowers for the flower color trait. | An organism's genotype for a gene is its combination of alleles for that gene. Pudge has one allele for a gray body (B) and one allele for a golden body (b). So, Pudge's genotype for the body color gene is Bb. |
Which statement describes the Eastern Siberian Taiga ecosystem? | [
"It has mostly small plants.",
"It has soil that is rich in nutrients.",
"It has long, cold winters and short, cool summers."
] | 2 | Figure: East Siberian Taiga.
The Eastern Siberian Taiga is a large forest that covers more than a quarter of Russia. It is home to brown bears, wolves, deer, and other organisms. | closed choice | grade6 | natural science | biology | Ecosystems | Describe ecosystems | An environment includes all of the biotic, or living, and abiotic, or nonliving, things in an area. An ecosystem is created by the relationships that form among the biotic and abiotic parts of an environment.
There are many different types of terrestrial, or land-based, ecosystems. Here are some ways in which terrestrial ecosystems can differ from each other:
the pattern of weather, or climate
the type of soil
the organisms that live there | A taiga is a type of ecosystem. Taigas have the following features: long, cold winters and short, cool summers, many evergreen trees, and soil that is poor in nutrients. So, the following statement describes the Eastern Siberian Taiga ecosystem: long, cold winters and short, cool summers, many evergreen trees, and soil that is poor in nutrients. It has long, cold winters and short, cool summers. The following statements do not describe the Eastern Siberian Taiga: long, cold winters and short, cool summers, many evergreen trees, and soil that is poor in nutrients. It has mostly small plants. It has soil that is rich in nutrients. |
|
Which property do these two objects have in common? | [
"sticky",
"salty"
] | 1 | Select the better answer. | closed choice | grade2 | natural science | physics | Materials | Compare properties of objects | An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells.
Different objects can have the same properties. You can use these properties to put objects into groups. | Look at each object.
For each object, decide if it has that property.
Potato chips have a salty taste. Both objects are salty.
A sticky object can stick to other things. Neither of the objects are sticky.
The property that both objects have in common is salty. |
|
Which property do these three objects have in common? | [
"soft",
"flexible",
"slippery"
] | 2 | Select the best answer. | closed choice | grade4 | natural science | physics | Materials | Compare properties of objects | An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it.
Different objects can have properties in common. You can use these properties to put objects into groups. Grouping objects by their properties is called classification. | Look at each object.
For each object, decide if it has that property.
A slippery object is hard to hold onto or stand on. All three objects are slippery.
A flexible object can be folded or bent without breaking easily. The wet ice cube is not flexible.
A soft object changes shape when pressed or squeezed. The butter is soft, but the wet ice cube is not.
The property that all three objects have in common is slippery. |
|
Not supported with pagination yet | Compare the motion of two mountain bikers. Which mountain biker was moving at a lower speed? | [
"a mountain biker who moved 190miles in 10hours",
"a mountain biker who moved 100miles in 10hours"
] | 1 | closed choice | grade2 | natural science | physics | Force and motion | Compare the speeds of moving objects | An object's speed tells you how fast the object is moving. Speed depends on both distance and time.
Distance tells you how far the object has moved. One unit used to measure distance is the mile.
Time tells you how long the object has spent moving. One unit used to measure time is the hour.
Think about two objects moving for the same amount of time. The object that is moving slower will go a shorter distance in that time. It is moving at a lower speed. | Look at the distance each mountain biker moved and the time it took to move that distance.
One mountain biker moved 100 miles in 10 hours.
The other mountain biker moved 190 miles in 10 hours.
Notice that each mountain biker spent the same amount of time moving. The mountain biker who moved 100 miles moved a shorter distance in that time. So, that mountain biker must have moved at a lower speed. |
|
Think about the magnetic force between the magnets in each pair. Which of the following statements is true? | [
"The magnitude of the magnetic force is greater in Pair 2.",
"The magnitude of the magnetic force is the same in both pairs.",
"The magnitude of the magnetic force is greater in Pair 1."
] | 0 | The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material. | closed choice | grade8 | natural science | physics | Velocity, acceleration, and forces | Compare magnitudes of magnetic forces | Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces.
The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other.
You can change the magnitude of a magnetic force between two magnets by changing the distance between them. The magnitude of the magnetic force is greater when there is a smaller distance between the magnets. | Distance affects the magnitude of the magnetic force. When there is a smaller distance between magnets, the magnitude of the magnetic force between them is greater.
There is a smaller distance between the magnets in Pair 2 than in Pair 1. So, the magnitude of the magnetic force is greater in Pair 2 than in Pair 1. |
|
Not supported with pagination yet | Would you find the word other on a dictionary page with the following guide words?
occur - oil | [
"yes",
"no"
] | 1 | yes or no | grade7 | language science | reference-skills | Reference skills | Use guide words | Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order.
To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on.
If one word is shorter, and there are no more letters to compare, then the shorter word comes first in alphabetical order. For example, be comes before bed. | Put the words in alphabetical order.
Since other is not between the guide words occur - oil, it would not be found on that page. |
|
Not supported with pagination yet | Select the vertebrate. | [
"white-spotted octopus",
"locust",
"whiptail lizard",
"peacock butterfly"
] | 2 | Hint: Mammals, birds, fish, reptiles, and amphibians are vertebrates. | closed choice | grade5 | natural science | biology | Classification | Identify vertebrates and invertebrates | Vertebrates and invertebrates are both groups of animals.
A vertebrate has a backbone. The backbone is made of many bones in an animal's back. A vertebrate's backbone helps connect the different parts of its body. In the drawings below, each vertebrate's backbone is colored orange.
An invertebrate does not have a backbone. In fact, invertebrates do not have any bones! Some invertebrates have an outer cover on their body called an exoskeleton. Other invertebrates have a soft body. | A whiptail lizard is a reptile. Like other reptiles, a whiptail lizard is a vertebrate. It has a backbone.
Like other octopuses, a white-spotted octopus is an invertebrate. It does not have a backbone. It has a soft body.
A peacock butterfly is an insect. Like other insects, a peacock butterfly is an invertebrate. It does not have a backbone. It has an exoskeleton.
A locust is an insect. Like other insects, a locust is an invertebrate. It does not have a backbone. It has an exoskeleton. |
Which property matches this object? | [
"translucent",
"colorful"
] | 1 | Select the better answer. | closed choice | grade3 | natural science | physics | Materials | Identify properties of an object | An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it. | Look at the object.
Think about each property.
A translucent object lets light through. But you cannot see clearly through a translucent object. The crayons are not translucent.
A colorful object has one or more bright colors. The crayons are colorful. |
|
Not supported with pagination yet | Select the elementary substance. | [
"methane (CH4)",
"water (H2O)",
"zinc (Zn)"
] | 2 | closed choice | grade5 | natural science | chemistry | Atoms and molecules | Identify elementary substances and compounds using chemical formulas | Every substance around you is made of one or more chemical elements, or types of atoms. Substances that are made of only one chemical element are elementary substances. Substances that are made of two or more chemical elements bonded together are compounds.
Every chemical element is represented by its own symbol. For some elements, the symbol is one capital letter. For other elements, the symbol is one capital letter and one lowercase letter. For example, the symbol for the element fluorine is F, and the symbol for the element beryllium is Be.
The symbol for each element in a substance is shown in the substance's chemical formula.
An elementary substance is represented by a chemical formula that contains only one symbol.
The symbol may be followed by a subscript. A subscript is text that is smaller and placed lower than the normal line of text. A subscript is included when the atoms in the elementary substance are bonded to form molecules. The subscript tells you the number of atoms in each molecule.
For example, the chemical formula for the elementary substance oxygen is O2. The formula has a subscript of 2. This subscript tells you that there are two atoms in the molecule represented by this chemical formula.
The chemical element represented by the symbol O is also called oxygen. So, the formula O2 tells you that each molecule of O2 contains two oxygen atoms.
A compound is represented by a chemical formula that contains multiple symbols.
For example, in the compound beryllium fluoride, there is one beryllium atom for every two fluorine atoms. This combination is shown in the compound's chemical formula, BeF2. In the formula, the symbol Be represents one beryllium atom. The symbol F followed by the subscript 2 represents two fluorine atoms. | Look at the chemical formula for each substance, and count the number of symbols in the formula. Then, decide if the substance is an elementary substance. The chemical formula for water contains two symbols: H for hydrogen and O for oxygen. So, water is made of two chemical elements bonded together. Substances that are made of two or more chemical elements bonded together are compounds. So, water is a compound, not an elementary substance. The chemical formula for zinc contains one symbol: Zn. So, zinc is made of one chemical element. Substances that are made of one chemical element are elementary substances. So, zinc is an elementary substance. The chemical formula for methane contains two symbols: C for carbon and H for hydrogen. So, methane is made of two chemical elements bonded together. Substances that are made of two or more chemical elements bonded together are compounds. So, methane is a compound, not an elementary substance. |
|
Not supported with pagination yet | What information supports the conclusion that Jada inherited this trait? | [
"Jada has green eyes like her biological mother.",
"Jada's neighbor has green eyes.",
"Jada and her biological father wear sunglasses when they go outside."
] | 0 | Read the description of a trait.
Jada has green eyes. | closed choice | grade7 | natural science | biology | Genes to traits | Inherited and acquired traits: use evidence to support a statement | Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways.
Inherited traits are passed down from biological parents to their offspring through genes. Genes are pieces of hereditary material that contain the instructions that affect inherited traits. Offspring receive their genes, and therefore gain their inherited traits, from their biological parents. Inherited traits do not need to be learned.
Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Parents do not pass acquired traits down to their offspring. | |
What is the capital of Ohio? | [
"Charleston",
"Columbus",
"Lincoln",
"Fargo"
] | 1 | closed choice | grade4 | social science | geography | State capitals | Identify state capitals of the Midwest | Columbus is the capital of Ohio. |
|||
Not supported with pagination yet | Which is a compound sentence? | [
"Bella was stung by a bee, so her finger is slightly swollen.",
"Mr. Estrada's afternoon lecture was about art and culture in Germany before World War II."
] | 0 | closed choice | grade6 | language science | grammar | Sentences, fragments, and run-ons | Is the sentence simple, compound, or complex? | A clause is a group of words that contains both a subject and a predicate.
An independent clause is a complete thought. It can stand alone as a sentence. A dependent clause is not a complete thought. It cannot stand alone as a sentence.
the oranges on our tree are ripe
The clause can stand alone. It is independent.
after we pick up Kevin from work
The clause cannot stand alone. It is dependent.
A simple sentence is made up of a single independent clause.
Ben and I spent all day relaxing by the pool.
Some simple sentences have introductory phrases, but the introductory phrase is part of the predicate.
In the winter, Ben usually wears his heavy coat.
Ben usually wears his heavy coat in the winter.
A compound sentence is made up of two independent clauses joined by a coordinating conjunction such as and, but, or, or so.
We saw a flash of lightning, and seconds later we heard the rumble of thunder.
A complex sentence is made up of an independent clause and a dependent clause. The dependent clause usually begins with a subordinating conjunction such as after, although, as, because, before, if, since, unless, until, when, or while.
If she ever gets the chance, Terri would love to visit the Egyptian pyramids. | The second sentence is the compound sentence. It is made up of two independent clauses joined by the coordinating conjunction so.
Bella was stung by a bee, so her finger is slightly swollen. |
|
Not supported with pagination yet | What is the volume of a soda bottle cap? | [
"12 liters",
"12 milliliters"
] | 1 | Select the better estimate. | closed choice | grade5 | natural science | units-and-measurement | Units and measurement | Choose metric units of volume | Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means.
Volume is a measurement of how much space something takes up.
There are many different units of volume. When you are using metric units, volume may be written in units of milliliters or liters.
There are 1,000 milliliters in 1 liter. So, 1 milliliter is much less than 1 liter.
A raindrop has a volume of about 20 milliliters, while a large soda bottle has a volume of 2 liters. The flask shown here measures volumes up to 500 milliliters. | The better estimate for the volume of a soda bottle cap is 12 milliliters.
12 liters is too much. |
Not supported with pagination yet | Which word would you find on a dictionary page with the following guide words?
cove - cylinder | [
"credit",
"cattle"
] | 0 | closed choice | grade5 | language science | reference-skills | Reference skills | Use guide words | Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order.
To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on.
If one word is shorter, and there are no more letters to compare, then the shorter word comes first in alphabetical order. For example, be comes before bed. | Put the words in alphabetical order.
Since credit is between the guide words cove - cylinder, it would be found on that page. |
|
Not supported with pagination yet | Which object has less thermal energy? | [
"a bowl of oatmeal at a temperature of 35°C",
"a bowl of oatmeal at a temperature of 40°C"
] | 0 | The objects are identical except for their temperatures. | closed choice | grade3 | natural science | physics | Heat and thermal energy | How is temperature related to thermal energy? | All solids, liquids, and gases are made of matter. Matter is made up of tiny particles that are always moving. The energy from the motion of these particles is called thermal energy.
Temperature measures how hot or cold matter is. If the particles in matter slow down, the temperature goes down. The matter now has both less thermal energy and a lower temperature. | The two bowls of oatmeal have the same mass but different temperatures. Since the 35°C bowl of oatmeal is colder than the 40°C bowl of oatmeal, it has less thermal energy. |
Which of these states is farthest east? | [
"Louisiana",
"North Dakota",
"North Carolina",
"Arizona"
] | 2 | closed choice | grade5 | social science | geography | Maps | Read a map: cardinal directions | Maps have four cardinal directions, or main directions. Those directions are north, south, east, and west.
A compass rose is a set of arrows that point to the cardinal directions. A compass rose usually shows only the first letter of each cardinal direction.
The north arrow points to the North Pole. On most maps, north is at the top of the map. | To find the answer, look at the compass rose. Look at which way the east arrow is pointing. North Carolina is farthest east. |
||
Which continent is highlighted? | [
"Antarctica",
"South America",
"Asia",
"Europe"
] | 1 | closed choice | grade5 | social science | geography | Oceans and continents | Identify oceans and continents | A continent is one of the major land masses on the earth. Most people say there are seven continents. | This continent is South America. |
||
Not supported with pagination yet | Which sentence is more formal? | [
"Kline Electronics has a reputation for responding real quick to customer concerns and questions.",
"Kline Electronics has a reputation for responding quickly to all customer concerns and questions."
] | 1 | closed choice | grade6 | language science | writing-strategies | Author's purpose and tone | Which sentence is more formal? | Formal writing is used for essays, business letters, and reports. The following types of informal language should be avoided in formal writing:
Type | Examples
slang | cool, awesome
idioms | knock your socks off
conversational language | gonna, kinda, yeah
abbreviated language | ASAP, FYI
overly simple or imprecise language | he got some stuff at the store
contractions | can't, won't
Contractions are not as informal as the other types, but they should be used sparingly in formal writing.
Compare the following sentences. The first is informal. The second is formal.
Informal: Yeah, ostriches can't fly, but they're awesome runners.
Formal: Though ostriches are flightless, they are remarkably adept runners.
| The second sentence is less formal. You can tell because it uses conversational language (real quick).
The first sentence uses formal language in place of the conversational language, so it is more formal overall. |
|
Not supported with pagination yet | Is the following trait inherited or acquired?
Jen has a scar on her left knee. | [
"acquired",
"inherited"
] | 0 | Hint: Most scars are caused by accidents during a person's life. | closed choice | grade3 | natural science | biology | Heredity | Identify inherited and acquired traits | Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways.
Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned.
Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Children do not inherit their parents' acquired traits. | Children do not inherit their parent's scars. Instead, scars are caused by the environment. People can get scars after they get hurt. So, having a scar is an acquired trait. |
Not supported with pagination yet | Using only these supplies, which question can Edmond investigate with an experiment? | [
"Do cloth towels dry faster if they are hung in the laundry room or in the backyard?",
"Does a small cloth towel or a large cloth towel dry faster when hung in the backyard?",
"When hung in the laundry room, do black cloth towels or white cloth towels dry more quickly?"
] | 0 | After Edmond cleans up a spill, he hangs a wet cloth towel in the laundry room. Two hours later, he notices that the towel has partially dried. He wonders what factors affect how cloth dries. So, he decides to design an experiment. He has the following supplies available:
two identical white cloth towels
water
a clothesline in the laundry room
a clothesline in the backyard | closed choice | grade7 | natural science | science-and-engineering-practices | Designing experiments | Identify questions that can be investigated with a set of materials | Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment.
Imagine that you are wondering if plants grow to different heights when planted in different types of soil. How might you decide what supplies are necessary to conduct this experiment?
First, you need to identify the part of the experiment that will be tested, which is the independent variable. This is usually the part of the experiment that is different or changed. In this case, you would like to know how plants grow in different types of soil. So, you must have different types of soil available.
Next, you need to identify the part of the experiment that will be measured or observed, which is the dependent variable. In this experiment, you would like to know if some plants grow taller than others. So, you must be able to compare the plants' heights. To do this, you can observe which plants are taller by looking at them, or you can measure their exact heights with a meterstick.
So, if you have different types of soil and can observe or measure the heights of your plants, then you have the supplies you need to investigate your question with an experiment! | |
Which month is the wettest on average in Christchurch? | [
"April",
"December",
"May"
] | 2 | Use the graph to answer the question below. | closed choice | grade3 | natural science | earth-science | Weather and climate | Use climate data to make predictions | Scientists record climate data from places around the world. Precipitation, or rain and snow, is one type of climate data.
A bar graph can be used to show the average amount of precipitation each month. Months with taller bars have more precipitation on average. | To describe the average precipitation trends in Christchurch, look at the graph.
Choice "Apr" is incorrect.
Choice "May" is incorrect.
Choice "Dec" is incorrect.
May has an average monthly precipitation of about 70 millimeters. This is higher than in any other month. So, May is the wettest month on average. |
|
Not supported with pagination yet | Which logical fallacy is used in the text?
Hazel has no school spirit—she never comes to any of our football games. | [
"red herring: the use of a completely unrelated topic or idea",
"false dichotomy: an argument that presents only two choices when more options exist"
] | 1 | closed choice | grade6 | language science | writing-strategies | Developing and supporting arguments | Classify logical fallacies | A strong argument uses valid reasoning and logic in support of a claim. When an argument or claim introduces irrelevant information or misrepresents the issues at hand, it may be committing a logical fallacy. Logical fallacies can hurt a writer's credibility and can lead readers to draw false conclusions.
A logical fallacy may present irrelevant information:
Fallacy | Description
ad hominem | a personal attack meant to discredit one's opponent
appeal to nature | an argument that assumes the natural choice is always the best choice
bandwagon fallacy | an argument that assumes the popular choice is always the best choice
circular reasoning | an argument that supports a claim with the claim itself
guilt by association | an unfair negative association with another person or group that is intended to discredit someone or something
red herring | the use of a completely unrelated topic in support of a claim
A logical fallacy may misrepresent the issues at hand:
Fallacy | Description
false causation | the assumption that because two things happened together, one caused the other
false dichotomy | an argument that presents only two choices when more options exist
hasty generalization | a very broad claim based on very little evidence
straw man | a misrepresentation of an opponent's position that makes it easier to argue against
| The text argues that Hazel doesn't have school spirit, because she doesn't go to football games. However, there may be a number of reasons why Hazel doesn't go to football games. This illustrates a type of logical fallacy known as a false dichotomy. |
|
Which of the following was a dependent variable in this experiment? | [
"the distance the footballs traveled",
"the air pressure in the footballs"
] | 0 | The passage below describes an experiment. Read the passage and think about the variables that are described.
Kamal noticed that some of the footballs his team used during practice were not fully inflated. He wondered whether fully inflated footballs would travel farther than footballs with a lower air pressure.
To find out, Kamal collected 20 standard footballs. He fully inflated ten of them to an air pressure of 13 pounds per square inch. He inflated the remaining ten to an air pressure of 10 pounds per square inch. Kamal used to launch a ball across a football field. He measured the distance the football traveled and then launched the next ball. Kamal repeated this with all 20 balls.
Hint: An independent variable is a variable whose effect you are investigating. A dependent variable is a variable that you measure.
Figure: a football launcher. | closed choice | grade6 | natural science | science-and-engineering-practices | Designing experiments | Identify independent and dependent variables | Experiments have variables, or parts that change. You can design an experiment to find out how one variable affects another variable. For example, imagine that you want to find out if fertilizer affects the number of tomatoes a tomato plant grows. To answer this question, you decide to set up two equal groups of tomato plants. Then, you add fertilizer to the soil of the plants in one group but not in the other group. Later, you measure the effect of the fertilizer by counting the number of tomatoes on each plant.
In this experiment, the amount of fertilizer added to the soil and the number of tomatoes were both variables.
The amount of fertilizer added to the soil was an independent variable because it was the variable whose effect you were investigating. This type of variable is called independent because its value does not depend on what happens after the experiment begins. Instead, you decided to give fertilizer to some plants and not to others.
The number of tomatoes was a dependent variable because it was the variable you were measuring. This type of variable is called dependent because its value can depend on what happens in the experiment. | ||
Not supported with pagination yet | What information supports the conclusion that Colleen acquired this trait? | [
"Colleen is in the Air Force. She flies a plane almost every day.",
"Colleen can fly a plane on cloudy days and at night.",
"A pilot taught Colleen how to fly a plane."
] | 2 | Read the description of a trait.
Colleen knows how to fly a plane. | closed choice | grade7 | natural science | biology | Genes to traits | Inherited and acquired traits: use evidence to support a statement | Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways.
Inherited traits are passed down from biological parents to their offspring through genes. Genes are pieces of hereditary material that contain the instructions that affect inherited traits. Offspring receive their genes, and therefore gain their inherited traits, from their biological parents. Inherited traits do not need to be learned.
Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Parents do not pass acquired traits down to their offspring. | |
What is the capital of New Hampshire? | [
"Montgomery",
"Concord",
"Manchester",
"Jackson"
] | 1 | closed choice | grade4 | social science | geography | State capitals | Identify state capitals of the Northeast | Concord is the capital of New Hampshire. |
|||
What is the capital of Pennsylvania? | [
"Trenton",
"Philadelphia",
"Harrisburg",
"Albany"
] | 2 | closed choice | grade4 | social science | geography | State capitals | Identify state capitals of the Northeast | Harrisburg is the capital of Pennsylvania. |
|||
Which solution has a higher concentration of green particles? | [
"Solution B",
"neither; their concentrations are the same",
"Solution A"
] | 0 | The diagram below is a model of two solutions. Each green ball represents one particle of solute. | closed choice | grade8 | natural science | chemistry | Solutions | Compare concentrations of solutions | A solution is made up of two or more substances that are completely mixed. In a solution, solute particles are mixed into a solvent. The solute cannot be separated from the solvent by a filter. For example, if you stir a spoonful of salt into a cup of water, the salt will mix into the water to make a saltwater solution. In this case, the salt is the solute. The water is the solvent.
The concentration of a solute in a solution is a measure of the ratio of solute to solvent. Concentration can be described in terms of particles of solute per volume of solvent.
concentration = particles of solute / volume of solvent | In Solution A and Solution B, the green particles represent the solute. To figure out which solution has a higher concentration of green particles, look at both the number of green particles and the volume of the solvent in each container.
Use the concentration formula to find the number of green particles per milliliter.
Solution B has more green particles per milliliter. So, Solution B has a higher concentration of green particles. |
|
Identify the question that Farid's experiment can best answer. | [
"Can pennies hold more drops of pure water or water mixed with hand soap?",
"Can pennies hold more drops of water mixed with dish soap or water mixed with hand soap?"
] | 0 | The passage below describes an experiment. Read the passage and then follow the instructions below.
Farid used a dropper to put equal-sized drops of pure water, one at a time, onto a penny. The drops stayed together and formed a dome on the penny's surface. Farid recorded the number of drops he could add before the water spilled over the edge of the penny. Then, he rinsed and dried the penny, and repeated the test using water mixed with hand soap. He repeated these trials on nine additional pennies. Farid compared the average number of pure water drops to the average number of water drops mixed with hand soap that he could add to a penny before the water spilled over.
Figure: a dome of water on the surface of a penny. | closed choice | grade7 | natural science | science-and-engineering-practices | Designing experiments | Identify the experimental question | Experiments can be designed to answer specific questions. How can you identify the questions that a certain experiment can answer? In order to do this, you need to figure out what was tested and what was measured during the experiment.
Imagine an experiment with two groups of daffodil plants. One group of plants was grown in sandy soil, and the other was grown in clay soil. Then, the height of each plant was measured.
First, identify the part of the experiment that was tested. The part of an experiment that is tested usually involves the part of the experimental setup that is different or changed. In the experiment described above, each group of plants was grown in a different type of soil. So, the effect of growing plants in different soil types was tested.
Then, identify the part of the experiment that was measured. The part of the experiment that is measured may include measurements and calculations. In the experiment described above, the heights of the plants in each group were measured.
Experiments can answer questions about how the part of the experiment that is tested affects the part that is measured. So, the experiment described above can answer questions about how soil type affects plant height.
Examples of questions that this experiment can answer include:
Does soil type affect the height of daffodil plants?
Do daffodil plants in sandy soil grow taller than daffodil plants in clay soil?
Are daffodil plants grown in sandy soil shorter than daffodil plants grown in clay soil? | ||
Not supported with pagination yet | Which figure of speech is used in this text?
Jeremiah and Kari have trouble working on projects together. Although Kari is very sociable and friendly, she's not exactly a team player. | [
"paradox",
"euphemism"
] | 1 | closed choice | grade9 | language science | figurative-language | Literary devices | Classify figures of speech: euphemism, hyperbole, oxymoron, paradox | Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive.
A euphemism is a polite or indirect expression that is used to de-emphasize an unpleasant topic.
The head of Human Resources would never refer to firing people, only to laying them off.
Hyperbole is an obvious exaggeration that is not meant to be taken literally.
I ate so much that I think I might explode!
An oxymoron is a joining of two seemingly contradictory terms.
Some reviewers are calling this book a new classic.
A paradox is a statement that might at first appear to be contradictory, but that may in fact contain some truth.
Always expect the unexpected. | The text uses a euphemism, a polite or indirect expression that is used to de-emphasize an unpleasant topic.
Not exactly a team player is an indirect way of saying that someone doesn't work well with others. |
|
Not supported with pagination yet | Would you find the word pink on a dictionary page with the following guide words?
parrot - property | [
"yes",
"no"
] | 0 | yes or no | grade8 | language science | reference-skills | Reference skills | Use guide words | Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order.
To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on.
If one word is shorter, and there are no more letters to compare, then the shorter word comes first in alphabetical order. For example, be comes before bed. | Put the words in alphabetical order.
Since pink is between the guide words parrot - property, it would be found on that page. |
|
Not supported with pagination yet | Does the sentence use a simile or a metaphor?
Mrs. Leonard is kind, and her heart is gold. | [
"metaphor",
"simile"
] | 0 | closed choice | grade5 | language science | figurative-language | Literary devices | Identify similes and metaphors | Similes and metaphors are figures of speech that compare two things that are not actually alike.
A simile compares two things by saying that one is like the other. Similes often use the words like and as.
My sister runs like a cheetah.
The sister's running and a cheetah's running are compared using the word like.
A cheetah is known for running fast, so the simile means that the sister also runs fast.
The cat's fur was as dark as the night.
The cat's fur and the night are compared using the word as.
The night is dark, so the simile means that the cat's fur is also dark.
A metaphor compares two things by saying that one of them is the other. Unlike similes, metaphors don't use the word like or as.
The snow formed a blanket over the town.
The snow and a blanket are compared without the word like or as.
A blanket is a large piece of cloth that completely covers a bed. The metaphor makes the reader imagine that the snow becomes a blanket, covering the town completely.
Using similes and metaphors in your writing can help you create an interesting picture for the reader. | Mrs. Leonard is kind, and her heart is gold.
The words heart and gold are compared without the word like or as. So, the sentence uses a metaphor. |
|
Think about the magnetic force between the magnets in each pair. Which of the following statements is true? | [
"The magnitude of the magnetic force is greater in Pair 2.",
"The magnitude of the magnetic force is the same in both pairs.",
"The magnitude of the magnetic force is greater in Pair 1."
] | 0 | The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material. | closed choice | grade7 | natural science | physics | Velocity, acceleration, and forces | Compare magnitudes of magnetic forces | Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces.
The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other.
You can change the magnitude of a magnetic force between two magnets by changing the distance between them. The magnitude of the magnetic force is greater when there is a smaller distance between the magnets. | Distance affects the magnitude of the magnetic force. When there is a smaller distance between magnets, the magnitude of the magnetic force between them is greater.
There is a smaller distance between the magnets in Pair 2 than in Pair 1. So, the magnitude of the magnetic force is greater in Pair 2 than in Pair 1. |
|
Which solution has a higher concentration of green particles? | [
"Solution A",
"Solution B",
"neither; their concentrations are the same"
] | 1 | The diagram below is a model of two solutions. Each green ball represents one particle of solute. | closed choice | grade6 | natural science | chemistry | Solutions | Compare concentrations of solutions | A solution is made up of two or more substances that are completely mixed. In a solution, solute particles are mixed into a solvent. The solute cannot be separated from the solvent by a filter. For example, if you stir a spoonful of salt into a cup of water, the salt will mix into the water to make a saltwater solution. In this case, the salt is the solute. The water is the solvent.
The concentration of a solute in a solution is a measure of the ratio of solute to solvent. Concentration can be described in terms of particles of solute per volume of solvent.
concentration = particles of solute / volume of solvent | In Solution A and Solution B, the green particles represent the solute. To figure out which solution has a higher concentration of green particles, look at both the number of green particles and the volume of the solvent in each container.
Use the concentration formula to find the number of green particles per milliliter.
Solution B has more green particles per milliliter. So, Solution B has a higher concentration of green particles. |
|
Not supported with pagination yet | Which figure of speech is used in this text?
The soul is born old but grows young. That is the comedy of life. And the body is born young and grows old. That is life's tragedy.
—Oscar Wilde, A Woman of No Importance | [
"chiasmus",
"apostrophe"
] | 0 | closed choice | grade12 | language science | figurative-language | Literary devices | Classify the figure of speech: anaphora, antithesis, apostrophe, assonance, chiasmus, understatement | Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive.
Anaphora is the repetition of the same word or words at the beginning of several phrases or clauses.
We are united. We are powerful. We are winners.
Antithesis involves contrasting opposing ideas within a parallel grammatical structure.
I want to help, not to hurt.
Apostrophe is a direct address to an absent person or a nonhuman entity.
Oh, little bird, what makes you sing so beautifully?
Assonance is the repetition of a vowel sound in a series of nearby words.
Try to light the fire.
Chiasmus is an expression in which the second half parallels the first but reverses the order of words.
Never let a fool kiss you or a kiss fool you.
Understatement involves deliberately representing something as less serious or important than it really is.
As you know, it can get a little cold in the Antarctic. | The text uses chiasmus, an expression in which the second half parallels the first but reverses the order of words.
The third sentence reverses the order of the words old and young relative to the first sentence. |
|
Does this passage describe the weather or the climate? | [
"weather",
"climate"
] | 0 | Figure: Tambor Beach, Costa Rica.
Tambor Beach is located in Costa Rica, a country in Central America. A temperature of 84°F was measured at Tambor Beach on Friday.
Hint: Weather is what the atmosphere is like at a certain place and time. Climate is the pattern of weather in a certain place. | closed choice | grade3 | natural science | earth-science | Weather and climate | Weather and climate around the world | The atmosphere is the layer of air that surrounds Earth. Both weather and climate tell you about the atmosphere.
Weather is what the atmosphere is like at a certain place and time. Weather can change quickly. For example, the temperature outside your house might get higher throughout the day.
Climate is the pattern of weather in a certain place. For example, summer temperatures in New York are usually higher than winter temperatures. | Read the passage carefully.
Tambor Beach is located in Costa Rica, a country in Central America. A temperature of 84°F was measured at Tambor Beach on Friday.
The underlined part of the passage tells you about the temperature at Tambor Beach on Friday. This passage describes the atmosphere at a certain place and time. So, this passage describes the weather. |
|
Not supported with pagination yet | Based on this information, what is this plant's phenotype for the fruit texture trait? | [
"bumpy fruit",
"smooth fruit"
] | 0 | In a group of cucumber plants, some individuals have bumpy fruit and others have smooth fruit. In this group, the gene for the fruit texture trait has two alleles. The allele for smooth fruit (f) is recessive to the allele for bumpy fruit (F).
A certain cucumber plant from this group has the homozygous genotype FF for the fruit texture gene. | closed choice | grade7 | natural science | biology | Genes to traits | Genetics vocabulary: dominant and recessive | All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different alleles, or forms, that can cause different versions of a trait.
For example, flower color is a trait in pea plants. The gene for this trait has two possible alleles. Each allele is represented by an uppercase or lowercase letter. The allele F is for purple flowers, and the allele f is for white flowers. Each pea plant has two alleles for the flower color gene—one allele inherited from each parent.
An organism's genotype for a gene is its combination of alleles for that gene. So, a pea plant may have a genotype of FF, Ff, or ff for the flower color gene.
An organism's phenotype for a trait is its observable version of that trait, which depends on the organism's combination of alleles. A pea plant may have a phenotype of purple flowers or white flowers for the flower color trait.
Some traits, like flower color in pea plants, are controlled by a single gene. Most plants and animals have a genotype made up of two alleles for these traits. These two alleles determine whether an organism is homozygous or heterozygous for the gene.
An organism with two identical alleles for a gene is homozygous for that gene. A pea plant with the genotype FF or ff is homozygous for the flower color gene.
An organism with two different alleles for a gene is heterozygous for that gene. A pea plant with the genotype Ff is heterozygous for the flower color gene.
The types of alleles in an organism's genotype determine the organism's phenotype. Some alleles have types called dominant and recessive. These two types can cause different versions of a trait to appear as the organism's phenotype.
A dominant allele causes its version of the trait to appear even when the organism also has a recessive allele for the gene. In pea plants, the F allele, which causes purple flowers, is dominant over the f allele. A pea plant with at least one F allele will have the F allele's version of the flower color trait. So, a plant with the genotype FF or Ff will have purple flowers.
A recessive allele causes its version of the trait to appear only when the organism does not have any dominant alleles for the gene. In pea plants, the f allele, which causes white flowers, is recessive to the F allele. A pea plant with only f alleles will have the f allele's version of the flower color trait. So, a plant with the genotype ff will have white flowers. | The cucumber plant's genotype for the fruit texture gene is FF. The cucumber plant's genotype of FF has only F allelles. The F allele is for bumpy fruit. So, the cucumber plant's phenotype for the fruit texture trait must be bumpy fruit.
To check this answer, consider whether the cucumber plant's alleles are dominant or recessive. The allele for smooth fruit (f) is recessive to the allele for bumpy fruit (F). This means F is a dominant allele, and f is a recessive allele.
The cucumber plant's genotype of FF has two dominant alleles. An organism with at least one dominant allele for a gene will have the dominant allele's version of the trait. So, the cucumber plant's phenotype for the fruit texture trait must be bumpy fruit. |
Will these magnets attract or repel each other? | [
"repel",
"attract"
] | 0 | Two magnets are placed as shown. | closed choice | grade5 | natural science | physics | Magnets | Identify magnets that attract or repel | Magnets can pull or push on other magnets without touching them. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes are called magnetic forces.
Magnetic forces are strongest at the magnets' poles, or ends. Every magnet has two poles: a north pole (N) and a south pole (S).
Here are some examples of magnets. Their poles are shown in different colors and labeled.
Whether a magnet attracts or repels other magnets depends on the positions of its poles.
If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract.
If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel. | To predict if these magnets will attract or repel, look at which poles are closest to each other.
The north pole of one magnet is closest to the north pole of the other magnet. Like poles repel. So, these magnets will repel each other. |
|
Is eclogite a mineral? | [
"no",
"yes"
] | 0 | Eclogite has the following properties:
solid
naturally occurring
not made by organisms
not a pure substance
no fixed crystal structure | yes or no | grade5 | natural science | earth-science | Rocks and minerals | Identify rocks and minerals | Properties are used to identify different substances. Minerals have the following properties:
It is a solid.
It is formed in nature.
It is not made by organisms.
It is a pure substance.
It has a fixed crystal structure.
If a substance has all five of these properties, then it is a mineral.
Look closely at the last three properties:
A mineral is not made by organisms.
Organisms make their own body parts. For example, snails and clams make their shells. Because they are made by organisms, body parts cannot be minerals.
Humans are organisms too. So, substances that humans make by hand or in factories cannot be minerals.
A mineral is a pure substance.
A pure substance is made of only one type of matter. All minerals are pure substances.
A mineral has a fixed crystal structure.
The crystal structure of a substance tells you how the atoms or molecules in the substance are arranged. Different types of minerals have different crystal structures, but all minerals have a fixed crystal structure. This means that the atoms or molecules in different pieces of the same type of mineral are always arranged the same way.
| Eclogite does not have all the properties of a mineral. So, eclogite is not a mineral. |
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Not supported with pagination yet | Which tense does the sentence use?
Scientists will measure the rainfall in Livingston. | [
"past tense",
"future tense",
"present tense"
] | 1 | closed choice | grade5 | language science | verbs | Verb tense | Is the sentence in the past, present, or future tense? | Present tense verbs tell you about something that is happening now.
Most present-tense verbs are regular. They have no ending, or they end in -s or -es.
Two verbs are irregular in the present tense, to be and to have. You must remember their forms.
Past tense verbs tell you about something that has already happened.
Most past-tense verbs are regular. They end in -ed.
Some verbs are irregular in the past tense. You must remember their past-tense forms.
Future tense verbs tell you about something that is going to happen.
All future-tense verbs use the word will.
Present | Past | Future
walk, walks | walked | will walk
go, goes | went | will go | The sentence is in future tense. You can tell because it uses will before the main verb, measure. The verb tells you about something that is going to happen. |
|
Which of the following could Lamar's test show? | [
"whether the filter was clogged",
"the amount of bacteria in the water before it was filtered",
"whether an inexpensive filter would become clogged more often"
] | 0 | People can use the engineering-design process to develop solutions to problems. One step in the process is testing if a potential solution meets the requirements of the design.
The passage below describes how the engineering-design process was used to test a solution to a problem. Read the passage. Then answer the question below.
Lamar was . At the plant, an expensive filter was used to remove disease-causing bacteria from the water. But over time, the filter would become clogged with bacteria. If the filter became clogged, the water would not move through quickly enough. Lamar had to decide when the filter was too clogged and needed to be replaced. So, during his inspection, Lamar checked the filter by measuring how quickly water moved through it.
Figure: an engineer at a water treatment plant. | closed choice | grade8 | natural science | science-and-engineering-practices | Engineering practices | Evaluate tests of engineering-design solutions | People can use the engineering-design process to develop solutions to problems. One step in the process is testing if a potential solution meets the requirements of the design. How can you determine what a test can show? You need to figure out what was tested and what was measured.
Imagine an engineer needs to design a bridge for a windy location. She wants to make sure the bridge will not move too much in high wind. So, she builds a smaller prototype, or model, of a bridge. Then, she exposes the prototype to high winds and measures how much the bridge moves.
First, identify what was tested. A test can examine one design, or it may compare multiple prototypes to each other. In the test described above, the engineer tested a prototype of a bridge in high wind.
Then, identify what the test measured. One of the criteria for the bridge was that it not move too much in high winds. The test measured how much the prototype bridge moved.
Tests can show how well one or more designs meet the criteria. The test described above can show whether the bridge would move too much in high winds. | ||
Not supported with pagination yet | What does the verbal irony in this text suggest?
According to Mr. Joyce's kids, his snoring is as quiet as a jackhammer. | [
"The snoring is loud.",
"The snoring is subtle."
] | 0 | closed choice | grade8 | language science | figurative-language | Literary devices | Interpret figures of speech | Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive.
Verbal irony involves saying one thing but implying something very different. People often use verbal irony when they are being sarcastic.
Olivia seems thrilled that her car keeps breaking down.
Each breakdown is as enjoyable as a punch to the face. | The text uses verbal irony, which involves saying one thing but implying something very different.
As quiet as a jackhammer suggests that the snoring is loud. A jackhammer is not quiet, and neither is Mr. Joyce's snoring. |
|
Not supported with pagination yet | Which tense does the sentence use?
Mr. Atkinson will deliver the envelope to Trent. | [
"future tense",
"past tense",
"present tense"
] | 0 | closed choice | grade5 | language science | verbs | Verb tense | Is the sentence in the past, present, or future tense? | Present tense verbs tell you about something that is happening now.
Most present-tense verbs are regular. They have no ending, or they end in -s or -es.
Two verbs are irregular in the present tense, to be and to have. You must remember their forms.
Past tense verbs tell you about something that has already happened.
Most past-tense verbs are regular. They end in -ed.
Some verbs are irregular in the past tense. You must remember their past-tense forms.
Future tense verbs tell you about something that is going to happen.
All future-tense verbs use the word will.
Present | Past | Future
walk, walks | walked | will walk
go, goes | went | will go | The sentence is in future tense. You can tell because it uses will before the main verb, deliver. The verb tells you about something that is going to happen. |
|
Not supported with pagination yet | What is the volume of a can of soda pop? | [
"320 liters",
"320 milliliters"
] | 1 | Select the better estimate. | closed choice | grade4 | natural science | units-and-measurement | Units and measurement | Choose metric units of volume | Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means.
Volume is a measurement of how much space something takes up.
There are many different units of volume. When you are using metric units, volume may be written in units of milliliters or liters.
There are 1,000 milliliters in 1 liter. So, 1 milliliter is much less than 1 liter.
A raindrop has a volume of about 20 milliliters, while a large soda bottle has a volume of 2 liters. The flask shown here measures volumes up to 500 milliliters. | The better estimate for the volume of a can of soda pop is 320 milliliters.
320 liters is too much. |
Not supported with pagination yet | Which figure of speech is used in this text?
Norma's phone slipped out of her pocket, landing in the toilet with a plop. | [
"verbal irony",
"onomatopoeia"
] | 1 | closed choice | grade9 | language science | figurative-language | Literary devices | Classify figures of speech: review | Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive.
Alliteration is the repetition of sounds at the beginning of nearby words.
What a lucky little lady you are!
An allusion is a brief reference to something or someone well known, often from history or literature.
"I'd better get home before I turn into a pumpkin!" Lila remarked.
An idiom is an expression that cannot be understood literally. Its meaning must be learned.
The assignment was a piece of cake.
A simile uses like or as to compare two things that are not actually alike.
The cat's fur was as dark as the night.
A metaphor compares two things that are not actually alike without using like or as.
The snow formed a blanket over the town.
Onomatopoeia involves using a word that expresses a sound.
The scrambled eggs hit the floor with a splat.
Personification is giving human characteristics to nonhuman things.
The trees danced in the wind.
A pun involves using a word or phrase in a humorous way that suggests more than one meaning.
A great new broom is sweeping the nation.
Verbal irony involves saying one thing but implying something very different. People often use verbal irony when they are being sarcastic.
Olivia seems thrilled that her car keeps breaking down.
Each breakdown is as enjoyable as a punch to the face. | The text uses onomatopoeia, a word that expresses a sound.
Plop represents the sound of the phone landing in the toilet. |
|
Not supported with pagination yet | Which tense does the sentence use?
The passengers will give Warren their tickets. | [
"present tense",
"future tense",
"past tense"
] | 1 | closed choice | grade3 | language science | verbs | Verb tense | Is the sentence in the past, present, or future tense? | Present tense verbs tell you about something that is happening now.
Most present-tense verbs are regular. They have no ending, or they end in -s or -es.
Two verbs are irregular in the present tense, to be and to have. You must remember their forms.
Past tense verbs tell you about something that has already happened.
Most past-tense verbs are regular. They end in -ed.
Some verbs are irregular in the past tense. You must remember their past-tense forms.
Future tense verbs tell you about something that is going to happen.
All future-tense verbs use the word will.
Present | Past | Future
walk, walks | walked | will walk
go, goes | went | will go | The sentence is in future tense. You can tell because it uses will before the main verb, give. The verb tells you about something that is going to happen. |
|
Which continent is highlighted? | [
"Europe",
"Asia",
"Australia",
"South America"
] | 0 | closed choice | grade8 | social science | geography | Physical Geography | Oceans and continents | A continent is one of the major land masses on the earth. Most people say there are seven continents. | This continent is Europe. |
||
What is the expected ratio of offspring with white spots to offspring with solid coloring? Choose the most likely ratio. | [
"4:0",
"3:1",
"1:3",
"2:2",
"0:4"
] | 4 | In a group of cows, some individuals have solid coloring and others have white spots. In this group, the gene for the coat pattern trait has two alleles. The allele for white spots (a) is recessive to the allele for solid coloring (A).
This Punnett square shows a cross between two cows. | closed choice | grade8 | natural science | biology | Genes to traits | Use Punnett squares to calculate ratios of offspring types | Offspring phenotypes: dominant or recessive?
How do you determine an organism's phenotype for a trait? Look at the combination of alleles in the organism's genotype for the gene that affects that trait. Some alleles have types called dominant and recessive. These two types can cause different versions of the trait to appear as the organism's phenotype.
If an organism's genotype has at least one dominant allele for a gene, the organism's phenotype will be the dominant allele's version of the gene's trait.
If an organism's genotype has only recessive alleles for a gene, the organism's phenotype will be the recessive allele's version of the gene's trait.
A Punnett square shows what types of offspring a cross can produce. The expected ratio of offspring types compares how often the cross produces each type of offspring, on average. To write this ratio, count the number of boxes in the Punnett square representing each type.
For example, consider the Punnett square below.
| F | f
F | FF | Ff
f | Ff | ff
There is 1 box with the genotype FF and 2 boxes with the genotype Ff. So, the expected ratio of offspring with the genotype FF to those with Ff is 1:2.
| To determine how many boxes in the Punnett square represent offspring with white spots or solid coloring, consider whether each phenotype is the dominant or recessive allele's version of the coat pattern trait. The question tells you that the a allele, which is for white spots, is recessive to the A allele, which is for solid coloring.
White spots is the recessive allele's version of the coat pattern trait. A cow with the recessive version of the coat pattern trait must have only recessive alleles for the coat pattern gene. So, offspring with white spots must have the genotype aa.
There are 0 boxes in the Punnett square with the genotype aa.
Solid coloring is the dominant allele's version of the coat pattern trait. A cow with the dominant version of the coat pattern trait must have at least one dominant allele for the coat pattern gene. So, offspring with solid coloring must have the genotype AA or Aa.
All 4 boxes in the Punnett square have the genotype AA or Aa.
So, the expected ratio of offspring with white spots to offspring with solid coloring is 0:4. This means that, based on the Punnett square, this cross will never produce offspring with white spots. Instead, this cross is expected to always produce offspring with solid coloring. |
|
Which country is highlighted? | [
"Saint Vincent and the Grenadines",
"Grenada",
"the Dominican Republic",
"Trinidad and Tobago"
] | 1 | closed choice | grade7 | social science | geography | The Americas: geography | Identify and select countries of the Caribbean | This country is Grenada. |
|||
Select the reptile below. | [
"dwarf crocodile",
"gorilla"
] | 0 | Reptiles have scaly, waterproof skin. Most reptiles live on land. A Galapagos giant tortoise is an example of a reptile. | closed choice | grade2 | natural science | biology | Classification | Identify mammals, birds, fish, reptiles, and amphibians | Birds, mammals, fish, reptiles, and amphibians are groups of animals. The animals in each group have traits in common.
Scientists sort animals into groups based on traits they have in common. This process is called classification. | A dwarf crocodile is a reptile. It has scaly, waterproof skin.
A gorilla is a mammal. It has fur and feeds its young milk. |
|
Not supported with pagination yet | What kind of sentence is this?
In the game today, Molly hit a home run with bases loaded! | [
"declarative",
"exclamatory",
"interrogative"
] | 1 | closed choice | grade10 | language science | punctuation | Sentences, fragments, and run-ons | Is the sentence declarative, interrogative, imperative, or exclamatory? | There are four kinds of sentences.
A declarative sentence is a statement and always ends with a period.
The nurse told Mr. Abrams to roll up his sleeve so that she could check his blood pressure.
An imperative sentence makes a request or a demand and usually ends with a period. If a demand shows strong feeling, it can end with an exclamation point.
For this assignment, use references to support your claims.
Don't drive so quickly in the construction zone!
An interrogative sentence asks a question and always ends with a question mark.
Given the recent critiques of her new strategic plan, do you think the CEO will reconsider the company's direction?
An exclamatory sentence is a statement that shows surprise or strong feeling. An exclamation always ends with an exclamation point.
I can't wait to travel through Europe this summer! | The sentence is a statement that shows strong feeling and ends with an exclamation point. It is an exclamatory sentence. |
|
Not supported with pagination yet | What do these two changes have in common?
rust forming on a bike frame
a penny tarnishing | [
"Both are chemical changes.",
"Both are only physical changes.",
"Both are caused by heating.",
"Both are caused by cooling."
] | 0 | closed choice | grade3 | natural science | chemistry | Physical and chemical change | Compare physical and chemical changes | Chemical changes and physical changes are two common ways matter can change.
In a chemical change, the type of matter changes. The types of matter before and after a chemical change are always different.
Some chemical changes are caused by heating or cooling. For example, burning a piece of paper is a chemical change caused by heating. When paper gets hot enough, it reacts with oxygen in the air and burns. The paper and oxygen change into ash and smoke.
In a physical change, the type of matter stays the same. The types of matter before and after a physical change are always the same.
A change of state is a type of physical change. Changes of state can be caused by heating or cooling. For example, ice melting is a physical change that can be caused by heating. Ice and liquid water are made of the same type of matter: water.
The law of conservation of mass says that all physical and chemical changes conserve mass. Conserve means to keep the same. So, the total mass before a physical or chemical change is equal to the total mass after the change. | Step 1: Think about each change.
Rust forming on a bike frame is a chemical change. The metal on the bike changes into rust. Metal and rust are different types of matter.
Metal turning less shiny over time is called tarnishing. A penny tarnishing is a chemical change. When air touches the penny, the surface of the penny changes into a different type of matter. This matter makes the penny dull.
Step 2: Look at each answer choice.
Both are only physical changes.
Both changes are chemical changes. They are not physical changes.
Both are chemical changes.
Both changes are chemical changes. The type of matter before and after each change is different.
Both are caused by heating.
Neither change is caused by heating.
Both are caused by cooling.
Neither change is caused by cooling. |
|
What is the capital of Massachusetts? | [
"Albany",
"Annapolis",
"Cambridge",
"Boston"
] | 3 | closed choice | grade4 | social science | geography | State capitals | Identify state capitals of the Northeast | Boston is the capital of Massachusetts. |
|||
Not supported with pagination yet | What do these two changes have in common?
mixing sand and gravel
crushing a mineral into powder | [
"Both are chemical changes.",
"Both are only physical changes.",
"Both are caused by cooling.",
"Both are caused by heating."
] | 1 | closed choice | grade4 | natural science | chemistry | Physical and chemical change | Compare physical and chemical changes | Chemical changes and physical changes are two common ways matter can change.
In a chemical change, the type of matter changes. The types of matter before and after a chemical change are always different.
Some chemical changes are caused by heating or cooling. For example, burning a piece of paper is a chemical change caused by heating. When paper gets hot enough, it reacts with oxygen in the air and burns. The paper and oxygen change into ash and smoke.
In a physical change, the type of matter stays the same. The types of matter before and after a physical change are always the same.
A change of state is a type of physical change. Changes of state can be caused by heating or cooling. For example, ice melting is a physical change that can be caused by heating. Ice and liquid water are made of the same type of matter: water.
The law of conservation of mass says that all physical and chemical changes conserve mass. Conserve means to keep the same. So, the total mass before a physical or chemical change is equal to the total mass after the change. | Step 1: Think about each change.
Mixing sand and gravel is a physical change. Together, the sand and gravel make a mixture. But making this mixture does not form a different type of matter.
Crushing a mineral into powder is a physical change. The mineral breaks into tiny pieces. But it is still made of the same type of matter.
Step 2: Look at each answer choice.
Both are only physical changes.
Both changes are physical changes. No new matter is created.
Both are chemical changes.
Both changes are physical changes. They are not chemical changes.
Both are caused by heating.
Neither change is caused by heating.
Both are caused by cooling.
Neither change is caused by cooling. |
Subsets and Splits