In a triaxial test a soil specimen was consolidated under a cell pressure of 100 kPa and a back pressure of 63 kPa. Then, under undrained conditions, the cell pressure was raised to 200 kPa resulting in a pore water pressure reading of 160 kPa; then (with the cell pressure remaining at 200 kPa) axial load was applied to give a deviator stress of 428 kPa and a pore water pressure reading of 367 kPa. Calculate the values of the pore pressure coefficients B, A and B. (B=0.97, A = 0.48 and B = 0.58