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: All cells have the small size in common.

Answer: What do all cells have in common?


Question: In pupa stage of their life cycle do insects begin developing their wings.

Answer: In what stage of their life cycle do insects begin developing their wings?


Question: The sun is directly over the equator during.

Answer:
When is the sun directly over the equator?