PLz help I will give brainliest

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.

How do your peer relationships affect your overall health status? what can you do to improve your peer relationships?

Plzzz answer both questions and i will give you 100 points