Two identical twins, Tui and Kui are playing on a large merry go round in an amusement park. The surface of merry go round is frictionless and is turning at a constant rate of revolution as the twins ride on it. Tui, sitting 2 m from the center of the merry go round, must hold onto one of the metal posts attached to the merry go round with a horizontal force of 90N to keep from sliding off. Kui is sitting at the edge, 4m from the center. With what horizontal force must she hold on to keep form falling off ?