Prob. 4.3-3. A solid, homogeneous, linearly elastic shaft of diameter d = 4.0 in. is subjected to a torque T = 120 kip. in. (Fig. P4.3-3). (a) Determine the maximum shear

stress in the shaft. (b) Determine the percentage of the total torque that is carried by an inner core of diameter d = 2.0 in. (shown darkly shaded in the figure). (c) Determine the percentage of the total weight of the shaft that lies within this inner core.