1) (25 points) Shaft BC is hollow with inner and outer diameters of 90 mm and 120mm, respectively. Shafts AB and CD are solid and of diameter d (Figure 1). For the loading shown, determine (a) the maximum and the minimum shearing stress in shaft BC, (b) the required diameter d of shafts AB and CD if the allowable shearing stress in these shafts is 65 MPa. 0.9 m A 0.7 m 05m 120 mm T₁ =6kN.m kNm/B TB = 14 kN.m C Tc = 26 kNm D T₁ =6kN.m Figure 1