The 66.5 kilogram climber is supported in the "chimney" by the friction forces exerted on his shoes and back. The static coefficients of friction between his shoes and the wall, and between his back and the wall, are 0.89 and 0.64, correspondingly. Suppose the walls are vertical and that the static friction forces are both at their maximum. Neglect his grip on the rope. Calculate the minimum normal force he must exert.