On a warm summer day, a large mass of air (atmospheric pressure 1.01×10⁵Pa) is heated by the ground to a temperature of 25.0°C and then begins to rise through the cooler surrounding air.
Calculate the temperature of the air mass when it has risen to a level at which atmospheric pressure is only 8.30×10⁴ Pa . Assume that air is an ideal gas, with γ=1.40. (This rate of cooling for dry, rising air, corresponding to roughly 1°C per 100 m of altitude, is called the dry adiabatic lapse rate.)