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 combines with rain to form acid rain? Answer: nitrogen and sulfur oxides

A: Courtesy of the U. S. EPA. Nitrogen and sulfur oxides combine with rain to form acid rain . Public Domain.
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Q: Question: The term "vapor" refers to the gas phase when it exists at a temperature below what? Answer: boiling temperature

A: for low temperatures, where the phase can change from a gas to a liquid. The term "vapor" refers to the gas phase when it exists at a temperature below the boiling temperature.
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Q: Question: What is the upper-most atmosphere known as? Answer: thermosphere

A:
The atmosphere is a big part of the water cycle. What do you think would happen to Earth's water without it?.
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