Write the coefficients of $x^2$ in each of the following:
$(i)$ $2+x^2+x$
$(ii)$ $2-x^2+x^3$

Verify whether the following is a zero of the polynomial indicated against it:
$p(x) = lx + m, \, x = -\frac{m}{l}$

Which of the following expressions are polynomials in one variable and which are not? State reasons for your answer: $4 x^{2}-3 x+7$.

Verify whether the following is a zero of the polynomial indicated against it:
$p(x) = 2x + 1, \, x = \frac{1}{2}$

Check whether the polynomial $q(t) = 4t^3 + 4t^2 - t - 1$ is a multiple of $2t + 1$.

Factorise the following using appropriate identities: $x^{2} - \frac{y^{2}}{100}$