Question 9
In triangle $ABC$, it is known that $AD$ and $BE$ are altitudes and $AP$ and $BQ$ are angle bisectors at $A$ and $B$, where $P$ and $Q$ lies on $CD$ and $CE$, respectively. If $\angle PAD=6^\circ$ and $\angle QBE=18^\circ$, what is the angle measure, in degrees, of $\angle BCA$?