6. 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 = 11.7 x 10-6/C and E = 200 GPa for steel. A= 1200 mm- A = 300 mm 1.2 m C 0.9 m 0.6 m B + -1.2 m