Question

A 1400 kilogram car crests a 3200 m pass in the mountains and briefly comes to rest. The car descends 1000 m before climbing and cresting a 2800 m pass. (a) neglecting friction, what should the speed of the car be at the top of the second pass? (b) find the actual speed of the car if the work due to non-conservative forces is -5×10^6 J.