Pure 2-methyl-2propanol has a freezing point of 25.50C, however it absorbs water (as an impurity) on exposure to humid air. If the freezing point og a 100.0g sample of 2-methyl-2-propanol is 24.59C, how many milligrams of water are present in sample(Kf(2methyl-2propanol=4.68Ckg/mol)