A great example of a physical boundary is a mountain. For example, the Pyrenees Mountains, which serve to separate France and Spain, are a physical boundary. So are the Ural Mountains which separate Europe and Asia. Along with mountains, oceans, seas, even deserts are examples of physical boundaries.
An average size apple weighs 6.4 ounces, which is equal to 180  grams. One apple contains approximately 91 calories and 3 grams of  dietary fiber.
One medium apple contains about 95 calories and 25 grams of carbohydrate (about the same amount as two slices of bread). If you are trying to watch your carbohydrate intake you may want to choose small sized (4 oz or the size of a tennis ball) apples to keep your carbohydrates to about 15 grams for about one serving of fruit.