$a) \: \left( \frac23 \cdot \frac53 \right)^2 =\left( \frac2 \cdot 53 \cdot 3 \right)^2 = \left( \frac109 \right)^2 = \frac10^29^2= \frac10081$ $b) \: \left[ \left( \frac-52 : \frac34 \right)^3 \right]^2=\left[ \left( \frac(-5)\cdot 42 \cdot 3 \right)^3 \right]^2=\left[ \left( \frac(-5)\cdot 2 (…)