Select the lightest pair of C12 to support the loads PD=100 k and PL = 135 k. The member is to be 35 ft long with both ends pinned and is to be arranged as shown in the Figure. Use A36 steel and design single lacing and end tie plates assuming that 3/4-in diameter bolts are to be used for connections. Assume that the bolts are located 1 in from the back of channels. Solve by LRFD procedures. Note: If the section provided is insufficient for strength requirements, select the nearest available economic section. I 9 in