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

Q: When magma heats groundwater, it may come to the surface as a hot spring or a geyser.

A: When magma heats groundwater, it may come to the surface as a hot spring or a what?
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Q: Population is an important level of organization in ecology and the unit of microevolution.

A: What is an important level of organization in ecology and the unit of microevolution?
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Q: The nucleus of an atom is positive due to the presence of positively charged protons.

A:
What part of an atom is positive due to the presence of positively charged protons?
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