Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: To determine the atomic weight of an element, you should add up protons and neutrons.

Answer: How do you determine the atomic weight of an element?


Question: Most of the digestion reactions occur in the small intestine.

Answer: Where do most of the digestion reactions occur?


Question: Removes unwanted substances does water treatment do to water.

Answer:
What does water treatment do to water?