For polynomial $p(x) = x^{3} - 3x^{2} + 8x + 12$,find the value of $p(-1)$.

Write the following cube in expanded form:
$(7x - 4y)^{3}$

Are the following expressions polynomials? Justify your answer:
$\frac{1}{x+1}$

Using a suitable identity,evaluate the following:
$999^{2}$

Write whether the statement is True or False. Justify your answer.
The degree of the sum of two polynomials each of degree $5$ is always $5$.

Without actually calculating the cubes,find the value of each of the following:
$(0.2)^{3} - (0.3)^{3} + (0.1)^{3}$