PLEASE HELP find the standard deviation​

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.

Which table represents points on the graph of h(x) = 3√-x+2?

Reagan lives five miles farther from school than vanessa lives. write an expression to describe how far reagan lives from school