Question 7
Rectangle $ABCD$ has $AD=18$ cm and $AB=12$ cm. Points $E,F$ lie on $AD,BC$, respectively, with $AE=BF=6$ cm. Diagonals $AC,BD$ meet at $O$ and meet $EF$ at $P,Q$, respectively. Find the total area of the shaded regions in the diagram, in cm².
