What do these two changes have in common?
sewing an apron
mixing sand and water

 - Both are chemical changes.
 - Both are only physical changes.
 - Both are caused by heating.
 - Both are caused by cooling.
Step 1: Think about each change.
Sewing an apron is a physical change. The fabric and thread that make up the apron get a new shape, but the type of matter in each of them does not change.
Mixing sand and water is a physical change. Adding water makes the sand wet. But both the sand and water are still made of the same type of matter as before.
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.