Question

water boils when it flows over molten rock at the base of a geyser. as the water boils, the rock beneath it cools down. complete the sentences. the rock heat, and the water heat as it boils. the water boiling is an process.

Explanation:

1. For the first blank: When the rock cools down, it means it is losing heat, so the rock "loses" heat.
2. For the second blank: When water boils, it needs to absorb heat from the rock, so the water "gains" heat.
3. For the third blank: A process where a substance (water here) absorbs heat to change its state (from liquid to gas during boiling) is an "endothermic" process because endothermic processes involve the absorption of heat.

Answer:

The rock \boxed{loses} heat, and the water \boxed{gains} heat as it boils. The water boiling is an \boxed{endothermic} process.