(Compound annuity) What is the accumulated sum of each of the following streams of payments? a. $520 a year for 10 years compounded annually at 10 percent. b. $108 a year for 6 years compounded annually at 8 percent. c. $35 a year for 11 years compounded annually at 11percent. d. $27 a year for 4 years compounded annually at 5 percent. a. What is the accumulated sum of $520 a year for 10 years compounded annually at 10 percent? (Round to the nearest cent.) b. What is the accumulated sum of $108 a year for 6 years compounded annually at 8 percent? (Round to the nearest cent.) c. What is the accumulated sum of $35 a year for 11 years compounded annually at 11percent? (Round to the nearest cent.) d. What is the accumulated sum of $27 a year for 4 years compounded annually at 5 percent? (Round to the nearest cent.)