13. A toy train is pulled to the right with a force of magnitude 12.0 N. The masses of each train are as follows: m1 = 5.50 kg, m2 = 5.30 kg, and m3 = 4.48 kg. Assume friction is negligible. a. Determine the acceleration of the train. [2T, 1C] m1 m2 m3 b. Determine the magnitude of the force of tension on each of the two connecting ropes. [4T, 2C]