6 A car of mass 1200 kg is driving along a straight horizontal road at a constant speed of \(15 \mathrm {~m} \mathrm {~s} ^ { - 1 }\). There is a constant resistance to motion of 350 N .

1. Find the power of the car's engine.
   The car comes to a hill inclined at \(1 ^ { \circ }\) to the horizontal, still travelling at \(15 \mathrm {~m} \mathrm {~s} ^ { - 1 }\).
2. The car starts to descend the hill with reduced power and with an acceleration of \(0.12 \mathrm {~ms} ^ { - 2 }\). Given that there is no change in the resistance force, find the new power of the car's engine at the instant when it starts to descend the hill.
3. When the car is travelling at \(20 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) down the hill, the power is cut off and the car gradually slows down. Assuming that the resistance force remains 350 N, find the distance travelled from the moment when the power is cut off until the speed of the car is reduced to \(18 \mathrm {~m} \mathrm {~s} ^ { - 1 }\).