Answer
a) $\frac{5184}{y^7}$
b) $1$
Work Step by Step
a) $(\frac{4}{y})^3(\frac{3}{y})^4=\frac{4}{y}\frac{4}{y}\frac{4}{y}\frac{3}{y}\frac{3}{y}\frac{3}{y}\frac{3}{y}=\frac{5184}{y^7}$
b) $(\frac{b^{-2}}{a^{-2}})(\frac{b}{a})^2=(\frac{b^{-2}}{a^{-2}})(\frac{b^2}{a^2})=1$
