Suppose that you are the treasurer of IBM with an extra US$1,000,000 to invest for six months. You are considering the purchase of U.S. T-bills that yield 1.810% (that's a six month rate, not an annual rate by the way) and have a maturity of 26 weeks. The spot exchange rate is $1.00 = 100, and the six month forward rate is $1.00 = 110. What must the interest rate in Japan (on an investment of comparable risk) be before you are willing to consider investing there for six months?

please please please shows your answer step by step! you should tell me how did you get your answer. Thanks.