1. What is the greatest common factor (GCF) of all the terms in the polynomial $18p^4q^2 - 30p^3q^3 + 6p^2q^4$?
2. Factor the polynomial completely by finding its greatest common factor: $14a^2b + 21ab^2 - 7ab$.
3. Which expression correctly shows the terms of $15m^3 + 5m^2 - 10m$ rewritten as products of the GCF?
4. Simplify the rational expression $\frac{4x-20}{x^2-5x}$. The simplified form is ___.
5. Which expression is the simplified form of $\frac{z^2-16}{z^2+8z+16}$?
6. Simplify the expression $\frac{p^2+2p-8}{p^2-p-2}$. The simplified form is ___.
7. To simplify the expression $\frac{m^2-4m}{7m-28}$, what is the common factor that can be canceled?
8. Simplify the rational expression $\frac{3w^2+9w-54}{2w+12}$ completely. The result is ___.