Three lines
$L_{1} : \vec{r} = \lambda\hat{i},\, \lambda\,\in\,R$
$L_{2} : \vec{r} = \hat{k} + \mu\hat{j},\,\mu\,\in\,R $ and
$L_{3} : \vec{r} = \hat{i} + \hat{j} + v\hat{k}, \,v \,\in\,R $
are given. For which point(s) $Q$ on $L_{2}$ can we find a point P on $L_{1}$ and a point R on $L_{3}$ so that P, Q and R are collinear?