$($a$)$ Create the matrix A in MATLAB.

$($b$)$ Make use of A and MATLAB function eye directly to generate a $5\backslash$times $5$ matrix B $=[$ Bmn $].$ The elements

of B are defined as follows:

Bmn $=$

$($

$0$ for m $=$ n

Amn for m $=$ n

$($c$)$ Make use of A or B and MATLAB function eye directly to generate a $5\backslash$times $5$ matrix C $=[$ Cmn $].$ The

elements of C are defined as follow