Have you ever watched your shadow as you walked along the street at night and observed how its shape changes as you move? Suppose a man who is 6 feet tall is standing below a lamppost that is 20 feet tall. The man is walking away from the lamppost at a rate of 5 feet per second.

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.

17 in long 1.3 ft wide and 8in high what is the volume

How to do this , and can some one explain