(4) The 200-mm-diameter rods AB and BC, having the original lengths shown, are joined at the collar B and fixed connected at their ends. If a torque is applied at collar B as shown, determine the maximum shear stress in rod AB. Take G - 30 GPa. B (a) 28.3 MPa (b) 35.4 MPa (c) 63.7 MPa (d) 55.2 MPa (e) 66.3 MPa 100 kNm 0.8 m