Question: FOREIGN EXCHANGE Kaitlin and her friend Emma returned to the United States from a tour of four cities: Oslo, Stockholm, Copenhagen, and Saint Petersburg. They now wish to exchange the various foreign currencies that they have accumulated for U.S. dollars. Kaitlin has 82 Norwegian krones, 68 Swedish krones, 62 Danish krones, and 1200 Russian rubles. Emma has 64 Norwegian krones, 74 Swedish krones, 44 Danish krones, and 1600 Russian rubles. Suppose the exchange rates are U.S. $0.1651 for one Norwegian krone, U.S. $0.1462 for one Swedish krone, U.S. $0.1811 for one Danish krone, and U.S. $0.0387 for one Russian ruble.
a. Write a 2 × 4 matrix A giving the values of the various foreign currencies held by Kaitlin and Emma. (Note: The answer is not unique.)
b. Write a column matrix B giving the exchange rate for the various currencies.
c. If both Kaitlin and Emma exchange all their foreign currencies for U.S. dollars, how many dollars will each have?