1. EcoSystems, Inc. is preparing a five-year plan. Today, your sales are $1,000,000. If the projected sales growth rate is 10% over the next five years, what will be the dollar amount of sales in year 5?
2. Kay and Arthur are newly married and just bought an apartment for $70,000. Since the apartment is very small, they hope to move into a house in five years. What will your apartment be worth in five years if the inflation rate is expected to be 8%?
3. Calculate the future value of an annuity of $5,000 for eight years, deposited at 6%.
4. Calculate the present value of an annuity of $3,900 for four years, assuming an opportunity cost of 10.
5. Cara has a seven-year loan, at 8%, with a bank that requires payments at the end of the year in the amount of $960.43.

Calculate the original principal amount. Use the corresponding formula.