The mass of a roller-coaster car, including its passengers, is 502 kg. Its speed at the bottom of the track is 20 m/s. The radius of this section of...

The mass of a roller-coaster car, including its passengers, is 502 kg. Its speed at the bottom of the track is 20 m/s. The radius of this section of the track is r1 = 27 m. Find the force that a seat in the roller-coaster car exerts on a 51-kg passenger at the lowest point.