Venant-kirchhoff material properties are given as e 600

Question

Consider a simple shear deformation of a square whose deformed geometry is given as

x₁= X₁ + αX₂, x₂ = X₂, x₃ = X₃

When the material is incompressible and St. Venant-Kirchhoff material properties are given as E = 600 MPa and ν = 0.49, write the expression of the S₁₂ component of the second Piola-Kirchhoff stress as a function of α.

In addition, write the expression of σ₁₂ of the Cauchy stress as a function of α. Plot S₁₂ and σ₁₂ in the range of α = [0.0 1.5].