If we assume that the atmosphere of the earth is an ideal gas mixture, then each component is described by a separate barometric equation. This model predicts that the concentrations of heavier molecules, and therefore their partial pressures, decreases faster than for lighter molecules as the altitude increases. Assume the ratio of partial pressure of nitrogen to oxygen is 4 at the surface of the earth, corresponding to 80% nitrogen by moles, and assume the temperature throughout the column is 25°C. Calculate the value of PN2/PO2 at the altitude of 10 km.