A rod consisting of two cylindrical portions AB and BC is restrained at both ends. Portion AB is made of brass (of E, = 15 x 10 psi, as = 11.6 x 10*/F) and portion BC is made of steel (of E.= 29 x 10 psi, a, = 6.5 x 10* /F). Knowing that the rod is initially unstressed, and ds = 3 in. diameter, d. = 2 in. diameter, a = 5 in. length as shown. 1) Determine the reaction force, R. at the end C by a temperature rise of 90F; 2) Calculate the coresponding thermal (normal) stresses induced in portions AB and BC; 3) Find the corresponding thermal expansion ur of point B.