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

Q: Diffraction is the phenomenon in which light and sound waves become circular at the point source of a barrier.

A: What is the phenomenon in which light and sound waves become circular at the point source of a barrier?
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Q: Covalent solutes separate into individual molecules when dissolved.

A: Covalent solutes separate into what when dissolved?
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Q: Heat and light two forms of energy could best be used to increase the temperature of a sheet of copper.

A:
Which two forms of energy could best be used to increase the temperature of a sheet of copper?
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