Question 1
Let $\angle xOy=90^\circ$. Inside it, draw rays $Oz,Ot$ such that $\angle xOz=30^\circ$ and $\angle tOy=30^\circ$. Take $K$ on ray $Ox$ with $OK=\sqrt3$. From $K$, draw the perpendicular to $Oz$, meeting it at $B$. Through $B$, draw the perpendicular to $Ot$, meeting ray $Oy$ at $D$. Find $OD$.
