In step P-28, chromatography is performed using a cation exchange column (SP Sepharose). This operation follows the enzymatic conversion of proinsulin to insulin and is intended to separate the insulin from the cleaved c peptide. The column is 2m long and 1m in diameter with a void fraction () of 0.35. The flow rate of the mobile phase through the column is 400L/hr. Insulin is eluted from the column at 1.5 column volumes (V0) and the yield is 95% at 1.7 column volumes. What is the standard deviation of the peak (SD)?(20%)