QuestionWhich of the following is equal to $\left[\frac{\left(x^{2} y^{3}\right)^{-2}}{\left(x^{6} y^{3} z\right)^{2}}\right]^{3}$ ? $\frac{\left(x^{2} y^{3}\right)^{-6}}{\left(x^{6} y^{3} z\right)^{6}}$ $\frac{1}{x^{8} y^{36} z^{6}}$ $\frac{\left(x^{2} y^{3}\right)}{\left(x^{6} y^{3} z\right)^{5}}$ $x^{-12} y^{-18}$