The boom AC is a 4-in. square steel tube with a wall thickness of 0.25 in. The boom is supported by the 0.5-in.-diameter pin at A, and the 0.375-in.-diameter cable BC. The working stresses are 25 ksi for the cable, 18 ksi for the boom, and 13.6 ksi for shear in the pin. Neglecting the weight of the boom, determine the largest safe load P that can be applied as shown.