The ladder shown is supported by a horizontal floor and a vertical wall. It is 12 ft long, weighs 30 lb (assumed to be concentrated at its mid-length), and supports a person weighing 175 lb at point D. The vertical wall is smooth and offers no frictional resistance. The coefficient of static friction at point A is 0.30. Calculate the minimum angle at which the ladder will stand without slipping to the left. P = 175 lb 3'-0", 3'-0" 6'-0" A W = 30 lb TIKSI B