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

Q: Microscopes were first developed in the early 1600s by eyeglass makers.

A: Microscopes were first developed in the early 1600s by this trade?
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Q: Protists are thought to be the oldest eukaryotes.

A: What is thought to be the oldest eukaryotes?
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Q: An electric stove changes electric current to thermal form of energy.

A:
An electric stove changes electric current to what form of energy?
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