Simplify Each Expression $(-6)^{-3}$ (B) $\left(25 x^{4} y^{2}\right)^{3 / 2}$ (C) $\left(\frac{16}{81}\right)^{-3 / 4}$

Short Answer

Simplify each expression. Assume that all variables represent positive real numbers.
(a) $(-6)^{-3}$
(b) $\left(25 x^{4} y^{2}\right)^{3 / 2}$
(c) $\left(\frac{16}{81}\right)^{-3 / 4}$