The tractor exerts a towing force T = 400 lb. Determine the normal reactions at each of th...

The tractor exerts a towing force T = 400 lb. Determine the normal reactions at each of the two front and two rear tires and the tractive frictional force F on each rear tire needed to pull the load forward at constant velocity. The tractor has a weight of 7500 lb and a center of gravity located at GT An additinal weight of 600 lb is added to its front having a center of gravity at GA. Take µs = 0.4. The front wheels are free to roll.