Question 120
Trapezoid $ABCD$, with bases $AB$ and $CD$, has side lengths $AB = 28$, $BC = 13$, $CD = 14$, and $DA = 15$. Let diagonals $AC$ and $BD$ intersect at $P$, and let $E$ and $F$ be the midpoints of $AP$ and $BP$, respectively. Find the area of quadrilateral $CDEF$.