(Compound annuity) What is the accumulated sum of each of the following streams of payments? a. $520 a year for 8 years compounded annually at 11 percent. b. $100 a year for 8 years compounded annually at 9 percent. c. $37 a year for 12 years compounded annually at 13percent. d. $28 a year for 5 years compounded annually at 4 percent. a. What is the accumulated sum of $520 a year for 8 years compounded annually at 11 percent? $ (Round to the nearest cent.)