\(a.\sqrt{0,01}-\sqrt{0,25}=\sqrt{0.1^2}-\sqrt{0,5^2}\)
\(=|0.1|-|0,5|=0,1-0,5=-0,4\)
\(\sqrt{0,01}-\sqrt{0,25}\)
\(=\sqrt{\frac{1}{100}}-\sqrt{\frac{25}{100}}\)
\(=\frac{1}{10}-\frac{5}{10}\)
\(=\frac{-2}{5}\)
\(0,5.\sqrt{100}-\sqrt{\frac{1}{4}}\)
\(=0,5.10-\sqrt{\frac{25}{100}}\)
\(=5-\frac{5}{10}\)
\(=\frac{9}{2}\)