Write the degree of each of the following polynomials

$8 x^{5}+3 x^{2}-4 x+7$

Classify the following polynomials as polynomials in one variable, two variables etc.

$x^{2}+x+1$

If $x+5$ is a factor of $x^{3}+13 x^{2}+a x+35$ find the value of $a$.

Factorise the following:

$16 x^{2}+4 y^{2}+9 z^{2}-16 x y-12 y z+24 x z$

From the following polynomials find out which of them has $(x+1)$ as a factor

$x^{3}+10 x^{2}+23 x+14$

Find the quotient and the remainder when $2 x^{2}-7 x-15$ is divided by

$x-2$