Ответ:

  1. \[\sqrt[3]{\frac{ab^2}{c}}\cdot\sqrt[3]{\frac{a^5b}{c^2}}=\sqrt[3]{\frac{a^6b^3}{c^3}}=\frac{a^2b}{c}.\]
  2. \[\frac{a^{-8}\cdot a^{\frac73}}{\frac1{a^{\frac13}}}=a^{-8+\frac73+\frac13}=a^{-\frac{16}{3}}=\frac1{a^{\frac{16}{3}}}.\]

Ответ: 1) \(\frac{a^2b}{c}\); 2) \(\frac1{a^{\frac{16}{3}}}\).