A three-dimensional state of stress at a point P in a body is given by the matrix:

4 O In [J] = [ 0 5 4 l ksi, rm 4 15 with respect to an x-y-z coordinate system. The unit vectors in the x-, y-, and :-directions are i, j, and k, respectively. Focus on a plane at point P whose unit outward normal is given by: 1 . . n: EO'l-J-l-k) a) Find the traction vector {(11) on the plane. Express the result in terms of the unknown stress component Ix: and the unit vectors Lj, and k. b) Find the value of the stress component In such that the normal stress on on the plane is equal to 10 ksi. c) For the value of II; found in part b), nd the shear stress I on the plane