A 2000 kg car is traveling at 20.0 m/s down a long mountain grade of 1.00%. The mountain road is 3.00 km long. The heat generated at the brakes due to friction heats up the brakes. The mass of the brake system is 20.0 kg and it has a specific heat of 0.200 kcal/kg 
What is the increase in the temperature of the brakes?
A. 22.3 
B. 35.1
C. 40.2
D. 45.2
E. 53.6
B. 35.1
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