Find (a) f(x+h), (b) f(x+h)-f(x),

Can someone answer these problems for me

Suppose that the price p (in dollars) and the weekly sales x (in thousands of units) of a certain commodity satisfy the demand equation 4p cubedplusx squaredequals38 comma 400. determine the rate at which sales are changing at a time when xequals80, pequals20, and the price is falling at the rate of $.20 per week.

What is the base of 1/9 to the power of 2