Factorise $16 x^{2}-40 x y+25 y^{2}$.

Without finding the cubes,factorise $(x-y)^{3}+(y-z)^{3}+(z-x)^{3}$.

Factors of $x^{2}-23x+120$ are.........

Show that $2x - 3$ is a factor of $x + 2x^3 - 9x^2 + 12$.

Classify the following as a constant,linear,quadratic,or cubic polynomial:
$5t - \sqrt{7}$

For the polynomial $\frac{x^{3}+2 x+1}{5}-\frac{7}{2} x^{2}-x^{6},$ write:
$(i)$ the degree of the polynomial
$(ii)$ the coefficient of $x^{3}$
$(iii)$ the coefficient of $x^{6}$
$(iv)$ the constant term