Before the 400 kN load is applied, the rigid platform rests on two steel bara, each of cross sectional area 1400mm^2, as shown in the figure. The cross sectional area of the aluminum bar is 2800 mm^2, Use E=200 GPa for steel and E = 70 GPa for aluminum. NEGLECT the weight of the platform A.) Compute the stress in the aluminum bar in Mpa after the 400 kN load is applied Choices: 45.64,16.30,40.62,14.51 B.) Compute the stress in the steel bar in Mpa

Before the 400 kN load is applied, the rigid platform rests on two steel bara, each of cross sectional area 1400mm^2, as shown in the figure. The cross sectional area of the aluminum bar is 2800 mm^2, Use E=200 GPa for steel and E = 70 GPa for aluminum. NEGLECT the weight of the platform A.) Compute the stress in the aluminum bar in Mpa after the 400 kN load is applied Choices: 45.64,16.30,40.62,14.51 B.) Compute the stress in the steel bar in Mpa Choices: 68.03,95.24,128.35,126.56 C.) Compute the shortening of the steel bar in mm. Choices: 0.125,0.085,0.113,0.158