Heldi Company is considering the ocquisation of a machine that costs 5488,000 . The machine is expected to have a useful life of 6 years, a negligible residual value, an annual net cash inflow of 5117,000 , and annual operating income of 585,459 . The estimated cash payback period for the machine i5 (round to one decimal polnt) 3. 5.0 years b. 42 years c. 5,7 years d. 6.5 years