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: Located above the stratosphere, what layer is the place where meteors burn up? Answer: mesosphere

A: The mesosphere is the layer above the stratosphere. Temperature decreases with altitude in this layer. Meteors burn up here.
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Q: Question: What remains a constant of radioactive substance over time? Answer: rate of decay

A: The rate of decay of a radioactive substance is constant over time.
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Q: Question: What does an array of radio telescopes collect? Answer: radio waves

A:
Radio telescopes collect radio waves and are sometimes used in large arrays.
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