66. Let a and b be real numbers. Given that the parabola equation on the coordinate plane 2 y =+ + x ax b intersects the x-axis intersect at P , Q , and PQ = 7 . If the intersection of the parabola ( ) 2 y x ax b =+ + + 2 and the x-axis is R, S, then RS = (A) 35 (B) 41 (C) 47 (D) 57