Please help I’m stuck on this question

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.

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base

What is the image of c for a 90° counterclockwise rotation about a? (3, 7) (-1, 3) (7, 3)