The rigid bar ABC is supported by a pin at B and two vertical steel rods. Initially the bar is horizontal and the rods are stress-free. Determine the stress in each rod if the temperature of the rod at A is decreased by 40C. Neglect the weight of bar ABC. Use a = 11.7x10-6 and E = 200 GPa for steel A = 1200 mm2. A = 300 mm? 1.2 m 0.9 m A B C -0.6 m 1.2 m