1. The oxygen (O2) we use in our body is derived from air, which is 21% O2. O2 from air dissolves and diffuses through a stationary layer of water coating our lungs. The water layer is 1 mm thick and O2 is totally removed by our blood circulation at the end of the water layer. O2 has a diffusivity of 1.97x10-5 cm/s in water. The solubility (c, in mol/m?) of O2 in water at the physiological temperature is given by c = p./0.7692, where pa (in atm) = partial pressure of O2 in air in contact with water. Calculate the flux of O2 transported through the lungs