Write a correct answer to the given question based on its associated fact. Make sure that your answer is contained in the associated fact. Don't be creative and introduce any new word that is not mentioned in the associated fact! Remember that the associated fact has been rearranged to form the question. So, the correct answer words must lie within the associated fact. The correct answer can be a word, phrase, or even a sentence.

Q: Fact: Heat falls from the equator to the poles. 
Question: What falls decreasingly on the earth from the equator to the poles?

A: heat.
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Q: Fact: a scale is used for measuring grams. 
Question: what is a scale used to measure?

A: grams.
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Q: Fact: Rain downwind from a coal-fired power plant is likely to change the color of litmus paper from blue to red. 
Question: How will the color of litmus paper change if rain downwind of a coal-fired plant falls on it?

A:
From blue to red.
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