At a point in a stress material, the normal tensile and shear stresses on a certain plane X-X are 95 MN/m2 and 65 MN/m2 respectively. The tensile stress on the plane of max shear is 55 MN/m2 . Find: (a) the principal stresses; (b) the max shear stress; (c) the direction of the plane X-X relative to the plane on which the major principle stress acts. Illustrate your answer by sketch