Consider the structure shown in Figure 1.1 below. The structure is assembled by an internal pin at B and a slotted connection at C. The two ends (A and D)

of the structure are fixed onto walls. Note that the slotted connection at C is friction less and cannot transfer any force in the sliding(horizontal) direction. As shown in the figure, the structure is subjected to a clockwise point moment (350 lb-ft) at H, an inclined point force (500 lb) at G, and a triangular distributed load (80Ib/ft) between B and G. Hint: Remember the connections at B and C cannot transfer moments. a) Find internal resultant normal forces, shear forces, and moments at E, F, and I. b) Determine the diameter of the circular pin at B, which is in a double shear connection, so that the average shear stress in the pin becomes 5 ksi (1ksi = 144,000 lb/ft²). Determine the diameter of the circular pin at the slot C, which is in a single shear connection, so that the average shear stress in the pin does not exceed 3 ksi.