12. Given △ABC with ∠B=60 ∘and ∠C=30 ∘ , let P,Q,R be points on sides BA,AC,CB respectively such that BPQR is an isosceles trapezium with PQ∥BR and BP=QR. Find the maximum possible value of [BPQR] 2[ABC] where [S] denotes the area of any polygon S.
