a) $$\left( \frac{4}{5} \right)^2 = \frac{4^2}{5^2} = \frac{16}{25}$$.
б) $$\left( \frac{11}{15} \right)^2 = \frac{11^2}{15^2} = \frac{121}{225}$$.
в) $$\left( \frac{7}{6} \right)^2 = \frac{7^2}{6^2} = \frac{49}{36} = 1 \frac{13}{36}$$.
г) $$\left( \frac{3}{8} \right)^2 = \frac{3^2}{8^2} = \frac{9}{64}$$.
д) $$\left( \frac{1}{3} \right)^3 = \frac{1^3}{3^3} = \frac{1}{27}$$.
Ответ: a) $$\frac{16}{25}$$; б) $$\frac{121}{225}$$; в) $$1 \frac{13}{36}$$; г) $$\frac{9}{64}$$; д) $$\frac{1}{27}$$