2. Consider the quadrilateral $A B C D$ where $m(\varangle A B C)=90^{\circ},[A C] \equiv[A D]$ and $m(\Varangle B A C) \equiv m(\Varangle C A D)=20^{\circ}$. Consider the point $E \in(A C)$ such that $D E \perp A C$. Determine the measure of the angle $\Varangle E B C$.