The homogeneous state of stress for a metal part undergoing plastic deformation is 
T=$\begin{bmatrix} 10 &5 &0 \\ 5&20 &0 \\ 0&0 &-10 \end{bmatrix}$
Where the stress component values are in MPa. Using von Mises yield criterion, the value of estimated shear yield stress, in MPa is
(a) 9.50 (b) 16.07
(c) 28.52 (d) 49.41