Question 14A segment through the focus $F$ of a parabola with vertex $V$ is perpendicular to $\overline{FV}$ and intersects the parabola in points $A$ and $B.$ What is $\cos(\angle AVB)?$$-\dfrac{3\sqrt{5}}{7}$$-\dfrac{2\sqrt{5}}{5}$$-\dfrac{4}{5}$$-\dfrac{3}{5}$$-\dfrac{1}{2}$