Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: Springs or geysers do we call heated groundwater that erupts from the ground under pressure.

Answer: What do we call heated groundwater that erupts from the ground under pressure?


Question: Changing the shape of an elastic material gives it potential energy.

Answer: Changing the shape of an elastic material gives it what type of energy?


Question: The pleura that surrounds the lungs consists of two layers.

Answer:
The pleura that surrounds the lungs consists of how many layers?