1. A box with mass M = 8 kg is placed on flat ground. One force F_a = 20 N pushes the block to the right, while another force F_b = 24 N pushes the block to the left. Ignore friction.
   1. Draw a diagram of the problem, with a coordinate system and known variables.
   2. Draw a free body diagram of the box, including all forces.1 sentence for each force explaining where it comes from.
   3. Use Newton's 2^nd law to determine the acceleration of the box.
   4. Calculate the speed of the box at t = 4 s.