TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: Most of the gray matter is on the surface of the brain, surrounding white matter.

SOLUTION: Most of the gray matter is on the surface of the brain, surrounding what other type of matter?

PROBLEM: How much is involved in the reaction does the coefficient in front of an element in a formula indicate.

SOLUTION: What does the coefficient in front of an element in a formula indicate?

PROBLEM: Pressure and vibration are examples of physical type of stimuli.

SOLUTION:
Pressure and vibration are examples of what type of stimuli?