Question

what do these two changes have in common?
mixing sand and gravel
mixing chocolate syrup into milk
select all that apply.
both are caused by cooling.
both conserve mass.
both are caused by heating.
both are only physical changes.

Explanation:

Mixing sand and gravel, and mixing chocolate syrup into milk are both physical changes (no new substances form). The law of conservation of mass applies to all physical changes—mass is neither created nor destroyed. Cooling/heating are not causes here.

Answer:

Both conserve mass., Both are only physical changes.