The RST Corp. is considering the purchase of some new equipment which will cost $120,000, last for 5 years, and generate after-tax cost savings of $45,000, $37,000, $25,000, $20,000, and $20,000 respectively per year. The firm's cost of capital is 10%. The IRR of this project is

a.-8.58%

b.8.36%

c.8.58%

d.12%

Please show work.