If 50.00mL of propylene glycol ( C3H8O2) has a mass of 51.80 grams, determine its density. To obtain the same antifreeze protection needs seventy six grams C3H8O2( propylene glycol) to substitute sixty two grams of C2H6O2 (ethylene glycol). Determine the mass of propylene glycol neded to substitute one gallon of ethylene glycol and also find out the volume of propylene glycol, required to get the same antifreeze protection as one gallon of ethylene glycol.express your answer in gallons?