A person creates an apparatus as shown in the figure to exercise the extensor muscle of the hand. It is given that OP=0.15 m, OQ=0.35 m, θ=30°, the weight of the lower arm =20 N, the center of mass of the lower arm is at point P, the magnitude of the applied tensile force F=50 N. If the extensor muscle is acting with a moment arm of 0.25 m, the muscle force required to hold the hand at the position shown in the figure is _________ N. Give your answer rounded off to the nearest integer.