Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Input: Consider Input: Pangaea began breaking apart 250 million years ago.

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


Input: Consider Input: Zero is the net force acting on an object when two equal forces are applied from opposite directions.

Output: What is the net force acting on an object when two equal forces are applied from opposite directions?


Input: Consider Input: Constructive interference is when two waves combine to create a larger wave.
Output: What is it called when two waves combine to create a larger wave?