Hayden Company is considering the acquisition of a machine that costs $460,000. The machine is expected to have a useful life of 6 years, a negligible residual value, an annual net cash flow of $89,000, and annual operating income of $75,650. What is the estimated cash payback period for the machine (round to one decimal points)?

a.1.2 years

b.5.2 years

c.7.3 years

d.6.1 years