For 8 years, Ruben invests $1100 at the end of each year into an account earning interest at 11% compounded annually. At the end of 8 years, he stops his annual payments and leaves the money in the account for an additional 4 years. a) What is the value of his investment at the end of 8 years? Answer : $ b) What is the value of his investment at the end of 12 years? Answer : $