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

[EX Q]: Stringed instruments can help show the relationship between tension and frequencies in strings.
[EX A]: Stringed instruments can help show the relationship between tension and what in strings?

[EX Q]: Chemical digestion mainly occurs in the small intestine.
[EX A]: Where does chemical digestion mainly occur?

[EX Q]: In physics, work means the use of force to move an object.
[EX A]:
In physics, work means the use of what to move an object?