Suppose the real exchange rate is 3/4 gallon of country a's gasoline per gallon of u. s. gasoline, a gallon of u. s. gasoline costs $3.00 u. s., and a gallon of gas in country a costs 6 units of their currency. what is the nominal exchange rate? a. 3/2 units of country a's currency per dollar. b. 8/3 units of country a's currency per dollar. c. 3/8 of a unit of country a's currency per dollar. d. none of the above is correct.