Boxes A and B are connected to each end of a light vertical rope, as shown in the following figure. A constant upward force 90.0 N is applied to box A. Starting from rest, box B descends 12.0 m in 3.50 s. The tension in the rope connecting the two boxes is 34.0 N (Figure 1). Part A What is the mass of box B ? Express your answer with the appropriate units. Submit Request Answer Part B What is the mass of box A ? Express your answer with the appropriate units. Submit Request Answer