${\left(6\text{cm}\right)}^2+{\left(8\text{cm}\right)}^2=c^2$  

$36{\text{cm}}^2+64{\text{cm}}^2=c^2$  

$c^2=100{\text{cm}}^2\mid \sqrt{}$  

$c=\sqrt{100}\text{cm}$   

$c=10\text{cm}$  

$O=10\text{cm}+6\text{cm}+8\text{cm}=24\text{cm}$  

 

$\text{I.}24\text{cm}:8\text{cm}=4\text{P}$   

$\text{II.}24\text{cm}:10\text{cm}\ne 3\text{F}$