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

Q: During the early paleozoic, the amount of carbon dioxide in the atmosphere was much greater compared to today.

A: During the early paleozoic, the amount of carbon dioxide in the atmosphere compared to today was?
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Q: When the smooth muscle relaxes, the arterioles dilate, allowing blood to enter the capillaries.

A: When the smooth muscle relaxes, the arterioles dilate, allowing blood to enter the what?
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Q: Internal body fluids link exchange surfaces to body cells else.

A:
Internal body fluids link exchange surfaces to what else?
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