Ответ:

а) \(\left(\frac{2}{7}\right)^2=\frac{2^2}{7^2}=\frac{4}{49}\).

б) \(\left(\frac{2}{3}\right)^3=\frac{2^3}{3^3}=\frac{8}{27}\).

в) \(\left(\frac{1}{5}\right)^3=\frac{1^3}{5^3}=\frac{1}{125}\).

г) \(3\frac{1}{3}=\frac{10}{3}\), поэтому \(\left(3\frac{1}{3}\right)^2=\left(\frac{10}{3}\right)^2=\frac{100}{9}=11\frac{1}{9}\).

Ответ: а) \(\frac{4}{49}\); б) \(\frac{8}{27}\); в) \(\frac{1}{125}\); г) \(11\frac{1}{9}\).