A 20-ft retaining wall is to be used to support a Terzaghi-Peck type 1 backfill (Figure 29). The wall cross section is similar to that shown in Illustration 3, except that the base is 8 ft instead of 10 ft. The backfill surface is level. Determine the factor of safety against overturning and against sliding (using a coefficient of friction between wall base and supporting soil, ) and the foundation pressure distribution (i.e., reaction against the base).