Triangles question bank (Maths)

In the figure,$OA = OB$ and $OD = OC$. Show that
$(i)$ $\Delta AOD \cong \Delta BOC$ and
$(ii)$ $AD \parallel BC$.

$AB$ is a line segment and line $l$ is its perpendicular bisector. If a point $P$ lies on $l$,show that $P$ is equidistant from $A$ and $B$.