A gravity dam of trapezoidal cross section with one face vertical and horizontal base is 22m high and has a thickness of 4m at the top. Water upstream stands 2m below the crest of the dam. The specific gravity of masonry is 2.4. A. Considering uplift pressure to vary uniformly from full hydrostatic pressure at the heel to zero at the toe: 1. Find the base width B of the dam so that the resultant force will act the extremity of the middle third near the toe. 2. Compute the maximum and minimum compressive stresses acting against the base of the dam.