You took an amazing class at the U that changed your life, so now you are going to invest for your retirement. Your tax bracket is 25% federal and 5% state. Your investment is in a federally and state tax free account that earns 11% each year, what interest rate are you effectively earning on your investment?
How much will you have effectively earned if you invest $4,000 each year for the next 35 years (please use the rate you got in question 2)?