A 35 feet diameter oil storage tank is built on a 100 ft thick soil layer. The tank exerts an uniform pressure of 1000 pcf on the ground surface. The groundwater table is 10 ft below the ground surface. The unit weight of soil above and below the groundwater table are 115 pcf 122 (10 points) Calculate and plot the initial vertical effective stress distribution in the soil below the center of the tank Calculate and plot the final vertical stress distribution. Graphs from parts(a) and (b) should be on the same plot. At what depth the increase in vertical stress is 10% of the initial effective verticals stress.