What do these two changes have in common?
stapling an envelope shut
erosion caused by wind

 - 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.
Stapling an envelope shut is a physical change. The envelope and the staple get new shapes. Both are still made of the same type of matter.
Erosion caused by wind is a physical change. The wind carries away tiny pieces of rock. But the pieces of rock do not become a different 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.