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

Ex Input:
Changing the shape of an elastic material gives it potential energy.

Ex Output:
Changing the shape of an elastic material gives it what type of energy?


Ex Input:
Lichens are not a single organism, but rather an example of a mutualism.

Ex Output:
Lichens are not a single organism, but rather an example of a what?


Ex Input:
A reservoir is part of a cycle that holds an element or water for a long period of time.

Ex Output:
What is part of a cycle that holds an element or water for a long period of time called?