It will cost $4,200 to acquire a small ice cream cart. Cart sales are expected to be $3,400 a year for five years. After the five years, the cart is expected to be worthless as that is the expected remaining life of the cooling system. What is the payback period of the ice cream cart?

6.18 years

0.25 years

0.81 years

4.05 years

1.24 years