If $A$ is a $n \times n$ matrix,then $adj(adj \,A) = $

If possible,using elementary row transformations,find the inverse of the following matrix:
$\left[\begin{array}{ccc}2 & 0 & -1 \\ 5 & 1 & 0 \\ 0 & 1 & 3\end{array}\right]$

If $A=\left[\begin{array}{ccc}1 & -2 & 2 \\ 0 & 2 & -3 \\ 3 & -2 & 4\end{array}\right]$,then $A \cdot \operatorname{adj}(A)$ is equal to

If $A$ is a $3 \times 3$ matrix and $|A|=2$,then $|\operatorname{Adj}(\operatorname{Adj} A)| \operatorname{Adj}(\operatorname{Adj} A) = $ (in $A$)

If $\operatorname{adj}\begin{bmatrix} 1 & 0 & 2 \\ -1 & 1 & -2 \\ 0 & 2 & 1 \end{bmatrix} = \begin{bmatrix} 5 & a & -2 \\ 1 & 1 & 0 \\ -2 & -2 & b \end{bmatrix}$, then $[a \quad b]$ is equal to

If $A = \begin{bmatrix} 2 & 3 \\ 4 & 6 \end{bmatrix}$,then ${A^{-1}} = $