The solubility of oxygen in lakes high in the rocky mountains is affected by the altitude. If the solubility of O2 from the air is 2.67 x 10^-4 M ar sea level (1.00 atm) and 25 degrees C, what is the solubility of O2 at an elevation of 12,000 ft where the atmospheric pressure is 0.657 atm? Assume the temperature is 25 degrees C, and that the mole fraction of O2 in air is 0.209 at both 12,000 ft and sea level.