Solute A is to be removed from an inert gas B in a multi-stage countercurrent absorption tower. The gas enters the tower at a rate of 200 kmol/h and contains 25 mol% A. The solvent enters the tower at a rate of 800 kmol/h and is initially free of solute. Determine (a) the concentration of the exiting gas stream and (b) the number of stages, if the exiting liquid stream contains 5.0 mol% A. The equilibrium relationship is VA 4.0XA. Assume that the carrier gas is insoluble in the solvent and the solvent is nonvolatile.