4-in square steel bar subjected to transverse

Question

4-in square steel bar subjected to transverse biaxial tensile stresses
Consider a 4-in square steel bar subjected to transverse biaxial tensile stresses of 20 ksi in the x direction and 10 ksi in the y direction. (a) Assuming the bar to be in a state of plane stress, determine the strain in the z direction and the elongations of the plate in the x and y directions. (b) Assuming the bar to be in a state of plane strain, determine the stress in the z direction and the elongations of the bar in the x and y directions. Let E= 30103 ksi and  = 0.25.