assume that a company is considering purchasing a machine for $41,250$ that will have a five$-$year useful life and no salvage value. the machine will lower operating costs by $17000$ per year. the company's rate of return is $18\%.$ use the present value of $$1$ or the present value of an annuity of $$1$ in arrears. the profitability index for this investment is closest to: $\mathrm{.}78,1\mathrm{.}25,1\mathrm{.}29,1\mathrm{.}35.$