KVPY SA Exam 2014 Question Paper

On the circle with center O, points A ,B are such that OA = AB . A point C is located on the tangent at B to the circle such that A and C are on the opposite sides o f the line OB and AB = BC . The line segment AC intersects the circle again at F . Then the ratio $\angle \mathit{B}\mathit{O}\mathit{F}:\angle \mathit{B}\mathit{O}\mathit{C}$ is equal to