We have that the formula for en interior angle of any polygon is
[tex]\alpha=180-\frac{360}{n}[/tex]where n is number of sides, so in this case n=14
[tex]\alpha=180-\frac{360}{14}\approx154.3[/tex]for the exterior angle we have
[tex]\frac{360}{n}=\frac{360}{14}\approx25.7[/tex]