A gaseous stream contains 3% mol of a solute A and a packed countercurrent absorption column is fed with a pure bound solvent. The column has a diameter of 1.5 meters. At the outlet of the absorber, the gas contains 0.2% mol of solute A and the liquid contains 1.4% mol of A. Consider that the mass transfer coefficient of the liquid film is kra = 24 gmol/s m, the mass transfer coefficient of the gas film is kya= 20 and the overall mass transfer coefficient of the liquid film is and the overall mass transfer coefficient is K,a = 15 gmol/km? Estimate the height of a transfer unit based on the overall resistance in the column.