physics
posted by mohd .
A truck engine transmits 28.0 { kW} (37.5 hp) to the driving wheels when the truck is traveling at a constant velocity of magnitude 60.0km/h( 37.3mi/h) on a level road.
1.Assume that 65% of the resisting force is due to rolling friction and the remainder is due to air resistance. If the force of rolling friction is independent of speed, and the force of air resistance is proportional to the square of the speed, what power will drive the truck at 30.00 km/h? Give your answer in kilowatts .
2.Assume that 65% of the resisting force is due to rolling friction and the remainder is due to air resistance. If the force of rolling friction is independent of speed, and the force of air resistance is proportional to the square of the speed, what power will drive the truck at 30.0 {\rm{ km/h}}? Give your answer in horsepower.
3.Assume that 65% of the resisting force is due to rolling friction and the remainder is due to air resistance. If the force of rolling friction is independent of speed, and the force of air resistance is proportional to the square of the speed, what power will drive the truck at 120.0 {\rm{ km/h}}? Give your answer in kilowatts.
4.Assume that 65% of the resisting force is due to rolling friction and the remainder is due to air resistance. If the force of rolling friction is independent of speed, and the force of air resistance is proportional to the square of the speed, what power will drive the truck at 120.0 {\rm{ km/h}}? Give your answer in horsepower.

I will be happy to critique your thinking.