You observe in the market today that the spot rate on Russian ruble is $101.14/P, the 180-day forward rate is $121.14/P. How much should the ruble exchange rate change in 180 days to prevent a profitable carry trade? a. A depreciation in yen relative to dollar by 19.77% b. An appreciation in yen relative to dollar by 19.77% c. A depreciation in yen relative to dollar by 9.89% d. An appreciation in yen relative to dollar by 9.89% e. Not enough information