The model airplane in Figure 5.6 is flying at a speed of 16.3 m/s on a horizontal circle of radius 19.6 m. The mass of the plane is 0.784 kg. The person holding the guideline pulls it in until the radius of the circle becomes 12.6 m. The plane speeds up, and the tension in the guideline becomes four times greater. What is the net work done on the plane?