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.
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Question: Question: What type of vents are giant tube worms found at? Answer: hydrothermal

Answer: Giant tube worms are found at hydrothermal vents. They get food from the chemosynthetic bacteria that live within them. The bacteria provide food; the worms provide shelter.

Question: Question: The only obvious difference between boys and girls at birth is what type of organs? Answer: reproductive

Answer: The only obvious difference between boys and girls at birth is their reproductive organs. However, even the reproductive organs start out the same in both sexes.

Question: Question: What is the concentration of gas molecules in the mesosphere? Answer: very low density

Answer:
The mesosphere has a very low density of gas molecules.