如图，直线$\mathit{AB}//\mathit{CD}$，直线$\mathit{EC}$分别与$\mathit{AB}$，$\mathit{CD}$相交于点$A$、点$C$，$\mathit{AD}$平分$\angle \mathit{BAC}$，已知$\angle \mathit{ACD}=80°$，则$\angle \mathit{DAC}$的度数为　　．