The normal boiling point of water under 1.00 atm pressure is 100.00 °C, or 373.15 K. The enthalpy of vaporization of water at this temperature is 40.68 kJ/mol. Use the Clausius-Clapeyron equation to predict the boiling point of water on the top of a mountain where the air pressure is 0.72 atm. Express your answer in °C.