The following cash flow has two rates of return. One of them is 8.510%. What is the other?

Year 0: $2021 Year 1: -$499 Year 2: -$8103 Year 3: $6798

a.) 39.074%

b.) 6.781%

c.) 2.334%

d.) 24.809%

e.) 62.441%

f.) 56.444%