Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Q: The water in some springs are hot because they're heated by hot magma.

A: The water in some springs are hot because they're heated by what?
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Q: The metallic bond is responsible for the properties of metals.

A: What is responsible for the properties of metals?
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Q: A lipid is one of a highly diverse group of compounds made up mostly of hydrocarbons.

A:
A lipid is one of a highly diverse group of compounds made up mostly of what?
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