I have a study guide that the answers were given but I would like to see the explanation

1.Fred has $1,500 today and wants $2,200 to buy some sound equipment. How long will Fred have to wait to buy the equipment if he earns 5.5 percent compounded annually on his money?

A.7.15 years

B.7.21 years

C.7.35 years

D.7.48 years

E.7.50 years

2.What is the future value of $13,400 invested for 6 years at 8 percent compounded monthly?

A.$19,963.93

B.$20,780.12

C.$21,264.12

D.$21,620.93

E.$21,654.26

3.What is the future value of $121,900 invested at 10 percent, compounded semi-annually for 25 years?

A.$1,320,750

B.$1,331,366

C.$1,348,002

D.$1,351,919

E.$1,397,876