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: Energy do ecosystems absorb on the earth.

Answer: What do ecosystems absorb on the earth?


Question: The sum of the masses of the atoms in the formula is referred to as molecular mass.

Answer: The sum of the masses of the atoms in the formula is referred to as what?


Question: Plants go through seasonal changes after detecting differences in day length.

Answer:
Plants go through seasonal changes after detecting differences in what?