$5.$ At a critical point in a $4340$ steel part is subjected to a state of stress in which $\backslash$sigma x $=6000$psi

and $\backslash$tau xy $=4000$psi, and the remaining stress components are all zero. For this state of stress,

determine the sum of the normal strains in the x$,$y$,$ and z directions; that is$,$ determine the

magnitude of $$x $+$y $+$z