a) \(\sqrt{81}=9\) = (-9) b) \(\sqrt{8100}=90=\left(-90\right)\) c) \(\sqrt{64}=8=\left(-8\right)\)
d) \(\sqrt{0,64}=0,8=\left(-0,8\right)\) e) \(\sqrt{1000000}=1000=\left(-1000\right)\)
g) \(\sqrt{0,01}=0,1=\left(-0,1\right)\) h) \(\sqrt{\dfrac{49}{100}}=\dfrac{7}{10}=\left(-\dfrac{7}{10}\right)\)
i) \(\sqrt{\dfrac{4}{25}}=\dfrac{2}{5}=\left(-\dfrac{2}{5}\right)\) k) \(\sqrt{\dfrac{0,09}{121}}=\dfrac{3}{110}=\left(-\dfrac{3}{100}\right)\)