A circular section tapering bar is rigidly fixed at both ends. The diameter change from 75 mm at one end to 150 mm at the other end, in a length of 1.2 m. If the temperature is raised by 32C, the maximum stress induced in the bar is (E = 200 GPa and -6 a = 12 x 10 C) (a) 76.8 N/mm (c) 153.6 N/mm (b) 19.2 N/mm (d) 158.8 N/mm