The model airplane in Figure 5.6 is flying at a speed of 14.6 m/s on a horizontal circle of radius 18.7 m. The mass of the plane is 0.918 kg. The person holding the guideline pulls it in until the radius of the circle becomes 14.3 m. The plane speeds up, and the tension in the guideline becomes four times greater. What is the net work done on the plane?