A farmer hitches her tractor to a sled loaded with firewood and
pulls it a distance of 20 m along level ground (Fig. 6.7a). The total
weight of sled and load is 14,700 N. The tractor exerts a constant
5000-N force at an angle of 36.9 above the horizontal. A 3500-N
friction force opposes the sled’s motion. Find the work done by
each force acting on the sled and the total work done by all the
forces.