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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 figures are polygons? select each correct answer. figure a figure b figure c figure d

Pr and pt a) pr = ps + pt b)pr = ps · pt c)(pr)2 = ps · pt