A section of a high speed test track is circular with a radius of curvature R = 1280 m.
At what angle of θ should the track be inclined so that a car traveling at 71.0 m/s (159 mph) would keep moving in a circle if there is oil on that section of the track, i.e., it would not slip sideways even with zero friction on that section. (Hint: The car's vertical acceleration is zero.)
