The United States purchased Alaska in 1867 for $7,200,000. Assume that federal tax revenue from the state of Alaska (net federal expenditures) is $56,500,000 in 2018 and that tax revenue started in 1868 and has steadily increased by 3% annually since then. Assume that the cost of capital (or interest rate) is 6%. What is the NPV of the Alaska purchase, assuming that you are in 1867 looking forward?