$a)\sqrt{36}=6,\text{bo}{6}^2=36$  

$b)\sqrt{\frac{25}{49}}=\frac{5}{7},\text{bo}{\left(\frac{5}{7}\right)}^2=\frac{25}{49}$  

$c)\sqrt{1\frac{40}{81}}=\sqrt{\frac{121}{81}}=\frac{11}{9}=1\frac{2}{9},\text{bo}{\left(\frac{11}{9}\right)}^2=\frac{121}{81}$  

$d)\sqrt{2,56}=\sqrt{\frac{256}{100}}=\frac{16}{10},\text{bo}{\left(\frac{16}{10}\right)}^2=\frac{256}{100}$  

$e)\sqrt[3]{216}=6,\text{bo}{6}^3=216$  

$f)\sqrt[3]{\frac{27}{64}}=\frac{3}{4},\text{bo}{\left(\frac{3}{4}\right)}^3=\frac{27}{64}$  

$g)\sqrt[3]{0,001}=0,1,\text{bo}{\left(0,1\right)}^3=0,001$  

$h)\sqrt[3]{3\frac{3}{8}}=\sqrt[3]{\frac{27}{8}}=\frac{3}{2},\text{bo}{\left(\frac{3}{2}\right)}^3=\frac{27}{8}$  

$i)\sqrt[3]{-512}=-8,\text{bo}{\left(-8\right)}^3=-512$   

$j)\sqrt[3]{-\frac{1}{125}}=-\frac{1}{5},\text{bo}{\left(-\frac{1}{5}\right)}^3=-\frac{1}{125}$