The Browns want to accumulate at least $150,000 at the time of their last deposit into a fund for their daughter's college by contributing an A amount to the account at the end of each year for eighteen years. What is the smallest annual payment A that will suffice if the college fund earns an effective level annual interest rate of 5%? If at the end of ten years the effective annual interest rate is announced to drop to 4.5%,

How much must the Browns' payments increase to reach their accumulation goal? Suppose the Browns want to continue making level payments except for a slightly reduced final payment.