Let PQR be a triangle of area ∆ with a = 2, b = 7/2 and c = 5/2, where a, b and c are lengths of the sides of the triangle opposite to the angle at P, Q and R respectively. Then (2sinP - sin2P)/(2sinP + sin2P) equals
(A) 3/4∆
(B) 45/4∆
(C) (3/4∆)2
(D) (45/4∆)2
