Ответ:

  1. \(\sqrt{\sqrt[3]{729}}=729^{\frac16}=(3^6)^{\frac16}=3\).
  2. \(\sqrt{\sqrt{1024}}=1024^{\frac14}=(2^{10})^{\frac14}=2^{\frac52}=4\sqrt2\).
  3. \(\sqrt[3]{\sqrt[3]{9}}\cdot\sqrt[9]{3^7}=3^{\frac29}\cdot3^{\frac79}=3\).
  4. \(\sqrt[4]{\sqrt[3]{25}}\cdot\sqrt[6]{5^5}=5^{\frac{2}{12}}\cdot5^{\frac56}=5\).

Ответ: 1) 3; 2) \(4\sqrt2\); 3) 3; 4) 5.