If $A = \begin{bmatrix} 3 & -5 \\ -4 & 2 \end{bmatrix}$,then $A^2 - 5A = $

If $A = \begin{bmatrix} 0 & 1 \\ 1 & 0 \end{bmatrix}$,then ${A^4} = $

Which of the following statements is not correct?

If $A = \begin{bmatrix} 1 & 0 \\ 1 & 1 \end{bmatrix}$ and $I = \begin{bmatrix} 1 & 0 \\ 0 & 1 \end{bmatrix}$,then which of the following holds for all $n \geq 2, n \in N$?

If $A_1, A_3, \dots, A_{2n-1}$ are $n$ skew-symmetric matrices of the same order,then $B = \sum_{r=1}^n (2r-1)(A_{2r-1})^{2r-1}$ will be:

Let $A = \begin{bmatrix} n & 0 & 0 \\ 0 & n & 0 \\ 0 & 0 & n \end{bmatrix}$ and $B = \begin{bmatrix} 0 & 0 & n \\ 0 & n & 0 \\ n & 0 & 0 \end{bmatrix}$. Then,$A^2 + B^2 + AB =$