NPV $-$ Arch, Inc., would like to purchase a blueprint machine for $$50,000.$ The machine is expected to have a life of $4$ years, and a salvage value of $$10,000.$ Annual maintenance costs will total $$14,000.$ Annual savings are predicted to be $$30,000$ in year $1,$$$37,000$ in year $2,$$$35,000$ in year $3,$ and $$32,000$ in year $4.$ The company's required rate of return is $11\%.$

a$.$ Find the net present value of this investment & determine the payback period

b$.$ Should the Arch purchase the machine? Explain, using one qualitative factor that may affect the decision.