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

Q: Surface tension is responsible for the fact that small insects can walk on water.

A: Surface tension is responsible for the fact that small insects can do this on water?
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Q: Solids are categorized by the forces holding the individual atoms, ions, or molecules together.

A: What is categorized by the forces holding the individual atoms, ions, or molecules together?
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Q: Woolly mammoths began to go extinct thousands of years ago because of hunting by humans.

A:
Why did woolly mammoths began to go extinct thousands of years ago?
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