3. In each situation below, a 10 kg box is at rest with a net force of zero. Beside each sketch, draw the free-body diagram for the box. Calculate and label the magnitude of the normal force. a. The 10 kg box is at rest on the floor. b. The 10 kg box is pushed down with an applied force of 50 N. F = 50 N c. The 10 kg box is pulled up with an applied force of 20 N. F = 20 N d. The 10 kg box is pressed against the ceiling with an applied force of 130 N. F = 130 N 2