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: Ionic compounds contain cations and anions rather than discrete neutral molecules.

Answer: Ionic compounds contain cations and anions rather than what?


Question: The force applied to an object is called stress.

Answer:
The force applied to an object is called?