In the diagram, O is the centre of a circle with radius 87 , and P and M lie on the circle. N is positioned inside the circle so that P N passes through O and is perpendicular to M N. If M N=63, what is the area of \triangle P M N ?
Answer Choices
A. 3370.5
B. 3496.5
C. 4725.0
D. 4630.5
E. 4126.5