9) You are free to invest in any currency. You can trade at the following prices: Spot rate, Russian ruble per dollar 20 RUB/S 6 month forward rate for rubles 22 RUB/S 6-month Russian interest rate 6-month U.S. interest rate 18% 6% a) Is covered interest arbitrage worthwhile? If so, explain the steps and compute the profit. Suppose that there is no forward market for the Russian ruble. Explain how an investor can engage in "uncovered" interest arbitrage and whether this is a true arbitrage or not. b)