Your child will go to college 12 years from now and will require $20,000, $21,000, $22,000, and $23,000 at the beginning of each year in school. In addition, you and your spouse plan to retire in 20 years. You want to have $75,000 available for each of your expected 15 years of retirement. These funds will need to be available at the beginning of each year. You currently have $15,000 that can be invested to meet these objectives. Assume you can earn an average 11 percent annual return in a mutual fund. How much must you invest at the end of each of the next 20 years in order to meet your financial objectives