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: Stirring, surface area, and temperature affect the rate at solute dissolves what occurs.

Answer: Stirring, surface area, and temperature affect the rate at which what occurs?

Question: You call materials that have high resistance to electric current electric insulators.

Answer: What do you call materials that have high resistance to electric current?

Question: Is the digestive tract of many sharks longer or shorter than many other vertebrates?

Answer:
Is the digestive tract of many sharks longer or shorter than many other vertebrates?