The equation below gives the maximum velocity in miles per hour that a vehicle can safely travel around a curve of radius r feet when friction is f. if the velocity is greater than vmax, the tires will slip. engineers find that under snowy conditions, vmax = 15 miles per hour for a freeway off-ramp that has a radius of 50 feet. to the nearest tenth, what is the coefficient of friction for the off-ramp in these conditions?