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: Constructive interference is when two waves combine to create a larger wave.

Answer: What is it called when two waves combine to create a larger wave?


Question: When magma heats groundwater, it may come to the surface as a hot spring or a geyser.

Answer: When magma heats groundwater, it may come to the surface as a hot spring or a what?


Question: Birds build nests to safe place.

Answer:
Why do birds build nests?