Which of the following statements are true? a. By building a plant in South Carolina, BMW has eliminated all exchange rate risk due to U.S. sales of its cars. b. An example of a natural hedge would be for a U.S. firm with sales in Canada (in which it receives Canadian dollars) to seek out a supplier in Mexico and pay in Mexican pesos. c. Porsche sells its cars in the U.S. in dollars but most of its costs are in euros. One way Porsche could hedge its risk is to acquire debt in dollars. This is one example of a matching strategy. d. All of the above are true