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: The discovery of ribozymes nullified the idea that all biological catalysts are proteins.

Answer: What nullified the idea that all biological catalysts are proteins?


Question: Do particles collide more in two reactants fluid they are both in fluid forms or solid forms.

Answer: Do particles collide more in two reactants when they are both in fluid forms or solid forms?


Question: Objects in motion that return to the same position after a fixed period of time are said to be in harmonic type of motion.

Answer:
Objects in motion that return to the same position after a fixed period of time are said to be in what type of motion?