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 the main function of the cardiovascular system? Answer: to transport

A: Many ecosystems have changed because of human actions. The human species is responsible for a range of environmental problems.
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Q: Question: What is another term for a hand lens? Answer: magnifying glass

A: An example of a lens is a hand lens, also called a magnifying glass. This type of lens makes objects look bigger than they really are. How do you think this happens?.
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Q: Question: The motion of stars in galaxies imply that there is about 10 times as much what as in the luminous objects we can see? Answer: mass

A:
Figure 6.18 The diagram shows angular momentum for a circular motion.
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