Assume that you contribute $6,000 per year to a retirement plan for 20 years. Then you are able to increase the contribution to $9,000 per year for another 20 years. Given an 8.0 percent interest rate, what is the value of your retirement plan after 40 years? Hint: This is equivalent to saving $6,000 each year for 40 years (from year 1 to year 40 ) and $3,000 each year for 20 years (from year 21 to year 40 ) $1,677,275 $1,634,199 $1,691,625 $1,688,012