4) √0,16/(2√0,04);

\(\sqrt{0.16}=0.4\), \(\sqrt{0.04}=0.2\).

\(\frac{\sqrt{0.16}}{2\sqrt{0.04}}=\frac{0.4}{2\cdot0.2}=\frac{0.4}{0.4}=1\).

Ответ: 1.