\[\frac{\sqrt{90}}{\sqrt{0,016}} = \sqrt{\frac{90}{0,016}} =\]
\[= \sqrt{\frac{90 \cdot 1000}{16}} = \sqrt{\frac{9 \cdot 10000}{16}} =\]
\[= \frac{3 \cdot 100}{4} = 3 \cdot 25 = 75\]