How do i solve this question?

A U.S. gallon is 231 in3. An Imperial gallon, used in England, Canada, and the British Commonwealth, is 277.42 in3. In Niagara Falls, New York, gasoline is $2.16 (U.S.) per gallon. Across the international bridge in Niagara Falls, Ontario, gasoline is $3.60 (Canadian) per Imperial gallon. Convert both prices to dollars per liter. If $1.00 (Canadian) = $0.65 (U.S.), on which side is gasoline cheaper, and by what percentage?