Joe has the winning Powerball lottery numbers which will pay out $15 million at the beginning of each of the next 30 years (reported prize of $450 million). Before claiming her prize, Dependable Insurance Company offers Joe $225 million today in exchange for her winning lottery ticket and prize payout. What rate of return would Dependable Insurance earn if Frieda accepts their offer?

a. 5.72

b. 6.12

c. 2.34

d. 5.22

e. 5.47