Ethanol C2h5oh And Gasoline Assumed To Be All Octane C8h18 Are Both Used As Auto

Ethanol (C2H5OH) and gasoline (assumed to be all octane, C8H18) are both used as automobile fuel. If gasoline is selling for $3.20/gal, what would the price of ethanol have to be in order to provide the same amount of heat per dollar? The density and delta H defrees F o octane are 0.7025 g/ml and -249.9 kJ/mol and of ethanol are 0.7894 and -277.0 kJ/mol, respectively. 1 gal = 3.785 L.