An 840-kg race car can drive around an unbanked turn at a maximum speed of 59 m/s without slipping. The turn has a radius of curvature of 155 m. Air flowing over the car's wing exerts a downward-pointing force (called the downforce) of 3200 N on the car.
(a) What is the coefficient of static friction between the track and the car's tires?
(b) What would be the maximum speed if no downforce acted on the car?