$\text{I.}$

$\frac{\text{n}-2}{\text{n}}\cdot {180}^o=\frac{12-2}{12}\cdot {180}^o=\frac{10}{12}\cdot {180}^o={150}^o$

${180}^o-{360}^o:12={180}^o-{30}^o={150}^o$ ${180}^o-{360}^o:12={180}^o-{30}^o={150}^o$

$\text{Odp. B, C, D}$

 

$\text{II.}$

$\frac{\text{n}\left(\text{n}-3\right)}{2}=\frac{9\left(9-3\right)}{2}=\frac{9\cdot 6}{2}=9\cdot \frac{3}{1}=27$

$\text{Odp. A, C}$

 

$\text{III.}$

$\text{Wzoˊr na sumę miar n-kąta foremnego:}$

$\left(\text{n}-2\right)\cdot {180}^o$

 

$\left(10-2\right)\cdot {180}^o=8\cdot {180}^o={1440}^o$

$\text{Odp. A, B, D}$