Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Q: The love canal tragedy was an infamous example of industrial waste dumping.

A: Love canal was an infamous example of what type of pollution?
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Q: The endocrine system produces hormones to regulate growth, development, and reproduction.

A: Which human organ system produces hormones to regulate growth, development, and reproduction?
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Q: Nitrogen oxide form(s) when nitrogen and oxygen combine at high temperatures.

A:
What forms when nitrogen and oxygen combine at high temperatures?
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