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22.4 The figure shows a mass m=5 kg sliding down a frictionless surface from an initial height h at point P. The mass slides down the surface and around a frictionless loop of radius R=2 m. If the normal force that the surface exerts on the mass when it is at the position Q is given by FN=180N, what is the height h? (A) 4.1 m (B) 7.2 m (C) 2.5 m h (D) 3.8 m (E) 5.7m R R