a) $\widehat{A}=180^{\circ}-70^{\circ}-35^{\circ}=75^{\circ}$
b)$\widehat{D}=180^{\circ}-65^{\circ}-25^{\circ}=90^{\circ}$
c)$\widehat{N}=180^{\circ}-131^{\circ}-21^{\circ}=28^{\circ}$
a) $\widehat{A}=180^{\circ}-70^{\circ}-35^{\circ}=75^{\circ}$
b)$\widehat{D}=180^{\circ}-65^{\circ}-25^{\circ}=90^{\circ}$
c)$\widehat{N}=180^{\circ}-131^{\circ}-21^{\circ}=28^{\circ}$