#### Answer

It is a polynomial.
Degree: 5
Leading term: $-3x^5$
Constant: 0
$G(x) = -3x^5 -18x^4 -36x^3 -24x^2$

#### Work Step by Step

First, we simplify:
$$ G(x)= -3x^2 (x+2)^3 \\G(x) = -3x^2 (x^{2} +4x +4) (x+2)^3 \\ G(x) = -3x^5 -18x^4 -36x^3 -24x^2$$
By definition, a polynomial is a function containing only terms where x is raised to a positive, integer power or constants. This is true, so we see that it is a polynomial. The degree is equal to the exponent of the term with the highest exponent, so the degree is 5. The term that has the highest degree, $-3x^5$, is always the leading term. Finally, there is no constant, so we call the constant 0.