What is the accumulated sum of each of the following streams of payments?

a. $520 a year for 9 years compounded annually at 9 percent.

b. $108 a year for 8 years compounded annually at 8 percent.

c. $32 a year for 13 years compounded annually at 11 percent.

d. $26 a year for 4 years compounded annually at 5 percent.