A box of weight w = 2 N accelerates down a rough plane that is inclined at an angle 30 degrees above the horizontal. The normal force acting on the box has a magnitude n = 1.7 , the coefficient of kinetic friction between the box and the plane is .3 and the displacement of the box is 1.8 m down the inclined plane.
What is the work done on the box by the force of kinetic friction?