If the beam A D is loaded as shown, determine the horizontal force P which must be applied...

If the beam A D is loaded as shown, determine the horizontal force P which must be applied to the wedge in order to remove it from under the beam. The coefficients of static friction at the wedge’s top and bottom surfaces are µCA = 0.25 and µCB = 0.35, respectively. If P = 0, is the wedge self-locking? Neglect the weight and size of the wedge and the thickness of the beam.