Ответ:

  1. \(\sqrt{108}\cdot\sqrt{3}=\sqrt{324}=18\).
  2. \(\sqrt{52}\cdot\sqrt{13}=\sqrt{676}=26\).
  3. \(\sqrt{160}\cdot\sqrt{250}=\sqrt{40000}=200\).
  4. \(\sqrt{0.4}\cdot\sqrt{4.9}=\sqrt{1.96}=1.4\).
  5. \(\frac{\sqrt{288}}{\sqrt{2}}=\sqrt{144}=12\).
  6. \(\frac{\sqrt{90}}{\sqrt{0.225}}=\sqrt{400}=20\).