A gravity retaining wall shown in the figure below is required to retain 5 m = = of soil. The backfill is a coarse grained soil with saturated unit weight -18 kN/m³, and friction angle of o 30 degrees. The existing soil below the base has the following properties; y = 20 kN/m³, 36 degrees. The wall is embedded Im into the existing soil, and a drainage system is provided as shown. The ground water table is at 4.5m below the base of the wall. Determine the stability of the wall. The unit weight of the wall material is 24 kN/m³. Ignore the drainage blanket in your analysis. B=0. 0-36 1m Drainage blanket 0.6m 4.2m 5m