A light triangular plate OAB is in a horizontal plane. Three forces, F1=5.2N, F2=9.9N, and F3=6.1N, act on the plate, which is pivoted about a vertical axes through point O. In the figure, F → 2 is perpendicular to OB. Consider the counterclockwise sense as positive. Find the sum of the torques about the vertical axis through point O, acting on the plate due to forces F1, F2, and F3.