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summit - n. the highest point of a mountain : the top of a mountain
crater - n. the area on top of a volcano that is shaped like a bowl
lava - n. melted rock from a volcano
vent - n. an opening through which air, steam, smoke, liquid, etc., can go into or out of a room, machine, or container
magma - n. hot liquid rock below the surface of the Earth
channel - n. a path, tube, or long narrow place where water flows
rapid - adj. happening in a short amount of time
