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The price of a Big Mac in Mexico is 75 pesos whereas the price of a Big Macs in the U.S. is $3. What is the exchange rate (Mexican pesos per dollar) that is consistent with the law of one price (purchasing power parity) applied to Big Macs? a) 1/15 pesos b) 45 pesos c) 25 pesos d) 1/25 pesos e) 15 pesos