2. Вычислите: а) \(2\cdot\left(\frac{12}{25}:\frac{6}{5}\right)\); б) \(\frac{14}{15}:\frac{2}{3}\cdot\frac{10}{21}\); в) \(\frac{2}{3}:\frac{3}{4}\cdot\frac{4}{5}\cdot\frac{5}{6}\).

1. а) \(2\cdot\left(\frac{12}{25}:\frac{6}{5}\right)=2\cdot\frac{12}{25}\cdot\frac{5}{6}=2\cdot\frac{2}{5}=\frac{4}{5}\).
2. б) \(\frac{14}{15}:\frac{2}{3}\cdot\frac{10}{21}=\frac{14}{15}\cdot\frac{3}{2}\cdot\frac{10}{21}=\frac{2}{3}\).
3. в) \(\frac{2}{3}:\frac{3}{4}\cdot\frac{4}{5}\cdot\frac{5}{6}=\frac{2}{3}\cdot\frac{4}{3}\cdot\frac{4}{5}\cdot\frac{5}{6}=\frac{16}{27}\).

Ответ: а) \(\frac{4}{5}\); б) \(\frac{2}{3}\); в) \(\frac{16}{27}\).