問答題 Some people read tea leaves to predict the future. We prefer hamburgers! The Economist began to calculate Big Mac index in 1986. They use it as a light-hearted guide to whether currencies are at their “correct” exchange rate. It is not intended as a precise predictor of exchange rates, but a tool to make economic theory more digestible. The following is the Big Mac Index in Apr. 25th 2002. 當以美元計價時，最便宜和最貴的漢堡包分別在哪里？從中可以得出有關(guān)這些國家匯率水平的什么結(jié)論？