The change in water vapor in a cloud is modeled by a polynomial function , c(x). describe how to find the x - intercepts of c(x) and how to construct a rough graph of c(x) so that the meteorologist can predict when there will be no change in the water vapor.

I honestly don't know! But to help you out, C(x) Is basically f(x) meaning a function of x. Y-coordinates are the functions of x,  so C(x) basically translates into "y-coordinate".So whenever you feel confused just remember that you are basically finding the matching x-coordinate for the y-coordinates! <3
P.S Whenever x changes y changes, not the other way around.