Given the system $\left\{ \begin{array} { l } - 2 x + y + k z = 1 \\ k x - y - z = 0 \\ - y + ( k - 1 ) z = 3 \end{array} \right.$, find:\ a) ( 1.25 points) Discuss it as a function of the parameter $k$.\ b) ( 0.5 points) Solve it for $k = 3$.\ c) ( 0.75 points) Solve it for $k = 3 / 2$ and specify, if possible, a particular solution with $x = 2$.