For the state of plane stress shown in the below figure, which of the following statements are true?
1
The maximum principal stress of the element is 75.2 MPa.
2
The maximum shear stress of the element is 60.2 MPa
3
The orientation of the principal planes is 41.63° & 131.63°
4
The shear stress exerted on the element when rotated anti clockwise through 30° is 18.97 MPa