The aerodynamic drag on a car depends on the "shape of the car. For example, the car (shown in figure) has a drag coefficient of 0.35 with the windows and roof closed. But with the windows and roof open, the drag coefficient increases to 0.45. With the windows and roof open, at what speed (in mph) is the amount of power needed to overcome aerodynamic drag the same as it is at 65 mph with the windows and roof closed? Assume the frontal area remains the same. Recall that power is force times velocity.
