Ответ:

  1. \(\sqrt{49}=7\), поскольку \(7^2=49\).
  2. \(\sqrt{0.09}=0.3\), поскольку \(0.3^2=0.09\).
  3. \(\sqrt{3\frac{6}{25}}=\sqrt{\frac{81}{25}}=\frac{9}{5}=1.8\).