A 85 kg skydiver parachutes from a stationary helicopter at a height of 1,200 m above the ground. After the skydiver reaches a predetermined speed, the parachute opens, slowing the skydiver down. With the parachute open, the skydiver reaches a terminal velocity of 3.5 m/s. Calculate the work done by air resistance during the descent from the height of the helicopter to the ground.

can someone answer these for me please? Thank you!

A car with mass 1520 kg is traveling down the highway at a speed of 18 m/s when the driver slams on the brakes due to an accident up ahead. The car eventually comes to rest.According to the work-energy theorem the work is related to the change in kinetic energy, Wnet = Δ KE = KEfinal - KEinitial.(a) Using the work-energy relationship, determine how much net work is done on the car from the brakes? Report the magnitude of the the work (positive value) even though the work from brakes will be negative since the car is slowing down._____ J(b) The brakes apply a force of 24000 N to the car in order to make it stop. Using the fact that W = F d and the fact that the you found the work done (magnitude) by the brakes in part (b), determine the stopping distance, d, of the car.____ m

A box of mass 4.0 kg is accelerated from rest across a floor at a rate of 2.0 m/s^2 for 9.0 s . a.) Find the net work done on the box. Express your answer to two significant figures and include the appropriate units. W= ________