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: Pangaea began breaking apart 250 million years ago.

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


Question: The mass remains the same does burning matter affect its mass.

Answer: How does burning matter affect its mass?


Question: A vapor light produces visible light by electroluminescence process.

Answer:
A vapor light produces visible light by what process?