I'm new to Air Canada, so please forgive me if the answer to this is obvious. When I look on the AC sight to determine the fee for checking a bag, it is listed as "$31.50 CAD/USD". This seems odd, given the difference in value between the two currencies. How is it determined determined which currency is charged? The flight will be originating in Canada, but I live in the U.S and will be booking from the U.S. -- will I automatically be charged the USD fee? Thanks in advance for any insight.