A rigid frame is fabricated by joining the three bars with pins at B, C, and D, as shown in figure. The frame is loaded by the 1000-lb force and the 1200-lb ft couple. The supports consist of a pin at A and a roller support at E. a. Draw the FBD of the frame, neglecting the weights of the members. b. How many unknowns are on the FBD? - 3 ft- 1.5 ft B F 1.5 ft 1000 lb 1200 lb ft A -2 ft→2 ft+2 ft+2 ft--