Ответ:

  1. \(0,5^8\cdot2^8=(0,5\cdot2)^8=1\).
  2. \(2^5\cdot0,5^5=(2\cdot0,5)^5=1\).
  3. \(\left(\frac13\right)^6\cdot6^6=\left(\frac63\right)^6=2^6=64\).
  4. \(0,125^9\cdot8^9=(0,125\cdot8)^9=1\).
  5. \(\left(1\frac79\right)^{11}\cdot\left(\frac9{16}\right)^{12}=\left(\frac{16}{9}\right)^{11}\cdot\left(\frac9{16}\right)^{12}=\frac9{16}\).
  6. \(0,25^{20}\cdot4^{18}=\left(\frac14\right)^{20}\cdot4^{18}=\frac1{4^2}=\frac1{16}\).

Ответ: 1) 1; 2) 1; 3) 64; 4) 1; 5) \(\frac9{16}\); 6) \(\frac1{16}\).