Which type of volcanic mountain has wide, gentle slopes?

Shield volcanoes

Explanation:

Shield volcanoes

Explanation:

Shield volcanoes erupt thin, 'runny', lava that forms a gently sloping structure. Where a volcano produces low viscosity, runny, lava it spreads far from the source forming a volcano with gentle slopes. This type is called a shield volcano. Mauna Kea and Mauna Loa are shield volcanoes.

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.

a physical change is being made.