Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.

Q: Question: What is used to fluoridate drinking water to promote dental health Answer: calcium fluoride

A: Calcium fluoride is used to fluoridate drinking water to promote dental health. Crystalline CaF 2 (d = 3.1805 3.
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Q: Question: What is the touch response in plants called? Answer: thigmotropism

A: The surface temperature of most stars is due to their size. Bigger stars produce more energy, so their surfaces are hotter. But some very small stars are very hot. Some very big stars are cool.
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Q: Question: What is the plasma membrane formed by? Answer: a phospholipid bilayer

A:
The plasma membrane is formed by a phospholipid bilayer.
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