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

Input: Consider Input: Wave amplitude and wavelength are two important measures of wave size.

Output: Wave amplitude and wavelength are two important measures of what?

Input: Consider Input: All enzymes have an optimal temperature and ph.

Output: All enzymes have an optimal temperature and what?

Input: Consider Input: In a medium, the closer the distribution of the material gets to equilibrium state, the slower the rate of diffusion becomes.
Output: In a medium, the closer the distribution of the material gets to what state, the slower the rate of diffusion becomes?