Write down the Python commands for each of the following operations:

$1.$ Create a row vector x of $5$ equally spaced elements between $2$ and $3.$

$2.$ Add $1$ to the second element

$3.$ Create a second row vector y of the same dimension with elements equal to the successive even integers starting with $4.$

$4.$ Create the matrix A$,$ whose first row is equal to x$,$ whose second row is a line of ones,

and whose third row is equal to y$.$

$5.$ Define a row vector z$,$ whose elements are equal to the mean value of the columns of

A$.$