Ответ:

  1. \(\left(1\dfrac16\right)^9\left(\dfrac67\right)^{10}=\left(\dfrac76\right)^9\left(\dfrac67\right)^{10}=\dfrac67\).
  2. \(5^{14}\cdot0.2^{12}=5^{14}\cdot\left(\dfrac15\right)^{12}=5^2=25\).
  3. \(\left(-1\dfrac13\right)^5\left(\dfrac34\right)^8=\left(-\dfrac43\right)^5\left(\dfrac34\right)^8=-\dfrac{3^3}{4^3}=-\dfrac{27}{64}\).

Ответ: 1) \(\dfrac67\); 2) 25; 3) \(-\dfrac{27}{64}\).