A rollercoaster car speeds up and down a hill past points a, b, and c as shown. The car has a mass of 500 kg and a speed of 25.0 m/s at point B where the track radius is 10 m. A: What is the maximum speed the car can have at point c, radius 19.6 m, for the gravitational force to hold it on the track? Use g = 10.0 m/s^2

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