Using elementary transformations, find the inverse of the matrix if it exists - $\begin{bmatrix} 2 & 0 & -1 \\ 5 & 1 & 0 \\ 0 & 1 & 3 \end{bmatrix}$

Question

$\begin{array}{1 1} (A) Does \;not\; exist \\ A^{-1}=\begin{bmatrix} -3 & -1 & 1 \\ -15& 6 & -5 \\- 5& -2 & 2 \end{bmatrix} \\ A^{-1}=\begin{bmatrix} 3 & 3 & 1 \\ -15& 8 & -5 \\ 5& -2 & 2 \end{bmatrix} \\ A^{-1}=\begin{bmatrix} 3 & -1 & 1 \\ -15& 6 & -5 \\ 5& -2 & 2 \end{bmatrix} \end{array}$