Isopropyl Ether (IPE) is used to separate acetic acid from an aqueous acetic acid solution containing 60% -wt acetic acid. Separation is done by extraction using a counter current flow direction. In the final extraction step, the concentration of acetic acid in raffinate is 10% by weight, while the extract contains 25% acetic acid. If the feed flow rate is 500 kg/hour, then calculate:

a. Flow rate of the aqueous phase (raffinate) and the ether phase (final extract, E1)(kg/hour)

b. The amount of solvent used (kg/hour)

c. The number of stages required for this separation