$\text{a)}{\left(\frac{4}{5}\right)}^2=\frac{16}{25}$  

$\text{b)}-{\left(1,5\right)}^2=-2,25$  

$\text{c)}{\left(-\frac{3}{2}\right)}^4=\frac{81}{16}=5\frac{1}{16}$  

$\text{d)}{\left(-2,2\right)}^2=4,84$  

$\text{e)}{\left(1\frac{2}{5}\right)}^2={\left(\frac{7}{5}\right)}^2=\frac{49}{25}=1\frac{24}{25}$  

$\text{f)}-{\left(-\frac{2}{3}\right)}^3=-\left(-\frac{8}{27}\right)=\frac{8}{27}$  

$\text{g)}{\left(-2\frac{2}{3}\right)}^3={\left(-\frac{8}{3}\right)}^3=-\frac{512}{27}=-18\frac{26}{27}$