HELP ME PLS ITS BEENA DAY

Astudent simplified a rational expression as shown.

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 businesses a country's economy? a. by investing in goods and services b. by increasing the unemployment rate c. by making profits