Factorise $: 121 x^{2}-289 y^{2}$

For the polynomial $p(x) = x^{2} - 7x + 12$,find the value of $p(2)$.

Classify the following as a constant,linear,quadratic,or cubic polynomial: $t^{2}$

Which of the following expressions is a polynomial? State the reason. If an expression is a polynomial,state whether it is a polynomial in one variable or not: $x^{2}+y^{2}+z^{2}+2xy+2yz+2zx$

The polynomial $p(x) = x^{4} - 2x^{3} + 3x^{2} - ax + 3a - 7$ when divided by $x + 1$ leaves the remainder $19$. Find the value of $a$. Also,find the remainder when $p(x)$ is divided by $x + 2$.

Give a possible expression for the length of a side of a square whose area is $(9x^2 + 30x + 25)$ square units, where $(x > 0)$.