Question

what do these two changes have in common? sanding a piece of wood stapling an envelope shut select all that apply. both are caused by heating. both are only physical changes. both are caused by cooling. both are chemical changes.

Explanation:

Sanding wood changes its physical appearance by removing material, and stapling an envelope shut is a physical - manipulation of the envelope. These are physical changes as no new substances are formed. Physical changes involve alterations in physical properties like shape, size, or texture without changing the chemical composition.

Answer:

Both are only physical changes.