Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: Force times distance is the equation for work.

Answer: Force times distance is the equation for what?


Question: Resistors connected end to end are said to be in series.

Answer: Resistors connected end to end are said to be in what?


Question: Solid -> liquid -> gas of these shows how frozen water changes as the temperature of the air increases.

Answer:
Which of these shows how frozen water changes as the temperature of the air increases?