7. In the arrangement shown in, the rigid bar is initially supported by the two outer steel rods 20 mm dia and 500 mm long. The central steel rod is 30 mm dia. but 0.1 mm shorter than the other two bars. Determine the maximum value of P so that the central bar is not stressed. If this maximum load is doubled, what will be the stresses in the three bars? E = 200 GPa. (Ans Max P: 25KN, Stress in each outer bar = 58.5 N/mm?, Stress in inner bar = 18.73 N/mm?) 0.1 mm