One of the difficulties of engaging in global trade is the constant shift in exchange rates. How much do exchange rates change over a 30-day period? Research this by choosing five currencies (say, the euro, the British pound, the Japanese yen, the Mexican peso, the Saudi Arabian riyal) and recording their exchange rates relative to the U.S. dollar for 30 days. The rates are available on the Internet at Yahoo Finance's Currency Center (http://finance.yahoo.com/ currency). At the end of the tracking period, choose a company and describe what effects the currency shifts you noted might have on this company's trade with each of the countries or areas whose currency you chose.