The tensile and shear strength of a composite are known to be F1t = 400MPa, F2t = 50MPa, F6 = 80MPa, and its compressive strength in both directions are twice stronger. Its elastic moduli are E11 = 50GPa, E22 = 10GPa, G12 = 8GPa, ν12 = 0.5. Two types of loading are to be applied to the compo i) σ11 and σ22; ii) σ11 and σ12. Based on the maximum stress and the maximum strain theories, plot the failure surface to indicate the boundary of safe and unsafe regions in the two-dimensional stress space for each of the two loading conditions.