A 24 inch square prestressed concrete pile is to be driven to a depth of 68 ft into the following soil profile. Depth (ft) 0-10 10-32 32-40 40-70 Soil Classification Silty clay Clayey silt Clay Clay Unit Weidth, y (lb/ft) 110 118 116 119 Undrained Shear Strength, su (lb/ft) 1000 1300 2000 2500 The groundwater table is at a depth of 5 ft. Using the Randolph and Murphy method with a factor of safety of 3.0, compute the ASD allowable downward load capacity, Pa-