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

Q: The human eye detect can detect three colors of light.

A: How many colors of light can the human eye detect?
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Q: 600 million many years ago may the earliest fungi have evolved.

A: How many years ago may the earliest fungi have evolved?
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Q: Rain is an example of liquid water.

A:
Which of these is an example of liquid water?
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