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: You call elements that contain only atoms of one type of element native elements.

Answer: What do you call elements that contain only atoms of one type of element?


Question: Pangaea began breaking apart 250 million years ago.

Answer: How many millions of years ago did pangaea begin breaking apart?


Question: Composition reaction type of reaction causes two substances to combine to make a single substance.

Answer:
What type of reaction causes two substances to combine to make a single substance?