$a)\sqrt{4\cdot 81}=\sqrt{4}\cdot \sqrt{81}=2\cdot 9=18$

$\sqrt{25\cdot 0,36}=\sqrt{25}\cdot \sqrt{0,36}=5\cdot 0,6=3$

$\sqrt{121\cdot 1000000}=\sqrt{121}\cdot \sqrt{1000000}=11\cdot 1000=11000$

 

$b)\sqrt[3]{8\cdot 27}=\sqrt[3]{8}\cdot \sqrt[3]{27}=2\cdot 3=6$

$\sqrt[3]{64\cdot 0,027}=\sqrt[3]{64}\cdot \sqrt[3]{0,027}=4\cdot 0,3=1,2$

$\sqrt[3]{125\cdot 1000000}=\sqrt[3]{125}\cdot \sqrt[3]{1000000}=5\cdot 100=500$

 

$c)\sqrt{\frac{4}{9}}=\frac{\sqrt{4}}{\sqrt{9}}=\frac{2}{3}$

$\sqrt{\frac{81}{25}}=\frac{\sqrt{81}}{\sqrt{25}}=\frac{9}{5}=1\frac{4}{5}$

$\sqrt{\frac{121}{144}}=\frac{\sqrt{121}}{\sqrt{144}}=\frac{11}{12}$

$\sqrt{\frac{361}{400}}=\frac{\sqrt{361}}{\sqrt{400}}=\frac{19}{20}$

 

$d)\sqrt[3]{\frac{27}{64}}=\frac{\sqrt[3]{27}}{\sqrt[3]{64}}=\frac{3}{4}$

$\sqrt[3]{3\frac{3}{8}}=\sqrt[3]{\frac{27}{8}}=\frac{\sqrt[3]{27}}{\sqrt[3]{8}}=\frac{3}{2}=1\frac{1}{2}$

$\sqrt[3]{\frac{1}{343}}=\frac{\sqrt[3]{1}}{\sqrt[3]{343}}=\frac{1}{7}$

$\sqrt[3]{\frac{125}{216}}=\frac{\sqrt[3]{125}}{\sqrt[3]{216}}=\frac{5}{6}$