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

[Q]: Most of the gray matter is on the surface of the brain, surrounding white matter.
[A]: Most of the gray matter is on the surface of the brain, surrounding what other type of matter?


[Q]: The high points in a transverse wave are called crests.
[A]: What are the high points in a transverse wave called?


[Q]: Energy is stored in a chemical substance between atoms.
[A]:
Where is energy stored in a chemical substance?