Question

Sublimation and boiling both happen at the surface of the substance.
a. True
b. False

Answer 1

This statement is: False

Boiling is vaporization that occurs both below and at the surface of the liquid.
However, evaporation happens at the surface of the substance.

So, if you need to correct this statement, the correction would be:
Sublimation and evaporation happen at the surface of the substance.