CIRCLE ALL ANSWERS AND PROVIDE UNITS 1. (20 points) Mohr's Circle and Stress Elements Oy An element in plane stress (shown above) is subjected to stresses Ox - 70 MPa, Oy, and Txy - 50 MPa. Using the Mohr's Circle equations, determine the following: a principal stresses, b. the maximum shear stress, C. the principal angle, d. If one of the principal stresses is negative, what does a negative stress mean? **Using just proper equations is acceptable, but Extra Credit will be given if Mohr's Circle is drawn out.