The data obtained from a rectangular strain gauge rosette attached to a stressed steel member are $\epsilon _{0}$= –220×10–6,$\epsilon _{45}$= 120×10-6 and $\epsilon _{90}$
= 220×10-6. Given that the value of E =2×105N/mm2 and Poisson’s Ratio m =0.3, calculate the values of principal stresses acting at the point and their directions.