Could anyone help me answer this physics question?

An underground tank with a capacity of 1850 L (1.85 m^3) is completely filled with ethanol that has an initial temperature of 19.1 C. After the ethanol has cooled off to the temperature of the tank and ground, which is 10.3 C, how much air space will there be above the ethanol in the tank? (Coefficient of volume expansion of ethanol is 75*10^5 (K)^-1, and ume that the volume of the tank doesn't change appreciably.)