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

Q: An object attached to a spring sliding on a frictionless surface is an uncomplicated type of simple harmonic oscillator.

A: An object attached to a spring sliding on a frictionless surface is an uncomplicated type of what device?
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Q: Virtually all aquatic organisms depend directly or indirectly on protists for food.

A: Virtually all aquatic organisms depend directly or indirectly on what for food?
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Q: Sodium chloride is an odorless white solid that is harmless unless consumed in large quantities.

A:
What is an odorless white solid that is harmless unless consumed in large quantities?
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