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

[EX Q]: The earth's magnetic poles have switched places repeatedly in the past.
[EX A]: The earth's magnetic poles have done what repeatedly in the past?

[EX Q]: The behavior of ideal gases is explained by kinetic molecular theory.
[EX A]: The behavior of ideal gases is explained by what theory of gases?

[EX Q]: Solution is the term for a homogeneous mixture of two or more substances.
[EX A]:
What is the term for a homogeneous mixture of two or more substances?