3. (30 points) The equilibrium partitioning of a peptide between an aqueous feed phase (x) and an organic solvent extract phase (v) has been found to be non-linear and can be described by the following equation: y = 0.7 1.3 It is desired to extract at least 80% of the peptide from a feed stream having a peptide concentration of 8.0 g/L. For a feed stream with a flowrate of 10 L/min and an extract stream with a flowrate of 8 L/min, determine the following: (a) (10 points) The concentration of peptide in the extract stream (y) needed to achieve the minimum separation specified above. (Hint: use the overall mass balance) *Important note for answering 3(b) and (c): In order to acquire a proper credit, label all but only important information on the graph very clearly. (b) (10 points) Plot and label the equilibrium curve and the operating line on the grid paper given on the next page. (c) (10 points) Using the diagram, determine the minimum integer number of equilibrium stages required to achieve the separation described above (assume countercurrent flow)