Which of the following is the actual length of a window that is 1 1/4 inches long on a drawing with a scale of 1 inch=6 feet?

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.

What is the slope of the line shown below?

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.