Ответ:

  1. \(\frac{2}{3}\cdot\frac{8}{13}=\frac{16}{39}\).
  2. \(2\frac{5}{11}-2\frac{4}{9}=\frac{27}{11}-\frac{22}{9}=\frac{243-242}{99}=\frac{1}{99}\).
  3. \(\frac{6}{7}:\frac{12}{35}=\frac{6}{7}\cdot\frac{35}{12}=\frac{5}{2}=2\frac{1}{2}\).

Ответ: а) \(\frac{16}{39}\); в) \(\frac{1}{99}\); д) \(2\frac{1}{2}\).