A solid 1.625-in.-diameter steel [G = 11,000 ksi] shaft is subjected to torques $T_B$ = 245 lb-ft and $T_D$= 85 lb-ft, acting in the directions shown. Assume a = 42 in., b = 72 in., and c = 24 in. If the allowable shear stress in the shaft is 14 ksi, determine the maximum torque $T_C$ that can be applied to the shaft.