The Toyota Prius has a drag coefficient of 0.25, a frontal area of 234 ft. and an empty weight of 3042 Ibf. Its rolling resistance coefficient is C, 0.03, that

is, the rolling resistance is 3 percent of the normal force on the tires. If rolling freely down a slope of 8 at an altitude of 500 m, calculate its maximum velocity, in mi/h.