EPA has set the maximum contaminant level (MCL) for toluene in water at 1 (mg/L), to comply with the 1974 Safe Drinking Water Act. A source of water containing 12.3 [mg/L] of toluene has been identified for drinking-water production. In a preliminary, lab-scale experiment, toluene will be stripped from the water with toluene-free air in a column packed with 5/8" plastic Pall rings at 25 [degree C] and 1 [atm]. The column has 15 [cm] of internal diameter and 1.15 [m] of packing height. The mass flow rates for the experiments are 2.4 [kg/min] and 6.5 [kg/min] for liquid and gas, respectively. At this conditions, the overall volumetric mass-transfer coefficient, in [mol/m^3 middot s], is given by: K_s a_b = 245 G_s^0.778 G_y^-0.05 where both mass velocities are in [kg/m^2 middot s]. Henry's constant and solubility for toluene in water at the experiments conditions are 6.64 times 10^-3 [atm middot m^3/mol] and 526 [mg/L], respectively. Toluene, water, and air have molar masses of 0.09214 [kg/mol], 0.01802 [kg/mol], and 0.029 [kg/mol], respectively. Density of water is 997 [kg/m^3]. Requirements: Please, compute or estimate the following: The height of an overall transfer unit based on liquid-phase mole fractions. The number of overall transfer units based on liquid-phase mole fractions. The outlet toluene mole fraction in the liquid. Is this result in compliance with EPA's MCL The outlet toluene mole fraction in the gas.