The continuously compounded interest rate on a 15-year default-free US dollar-denominated bonds is 0.5% per annum. The continuously compounded interest rate on 15-year default-free Euro-denominated bonds is 0.2% per annum. There are no transactions costs. The current exchange rate is $1.50 US for 1 Euro. There will be arbitrage opportunities unless a 15-year American-style call option on 500,000 Euro with an exercise price of US $750,000 is worth at least