Paf is a small country whose currency is the pif. Twenty years ago, the exchange rate with the U.S. dollar was 2.5 pifs per dollar, and the inflation indexes were equal to 100 in both the United States and Paf. Now, the exchange rate is 0.95 pifs per dollar, and the inflation indexes are equal to 450 in the United States and 230 in Paf. a. What should the current exchange rate be if PPP prevailed? b. Is the pif over- or undervalued according to PPP?