Teduie Construction made an investment in a machine that is used for road construction two years ago. Due to rapidly changing technology, a new machine is challenging this 2-year-old machine. The chief engineer at Teduie Construction has collected the following information relevant to the challenger: First cost: $50,000 Future market values: decreasing by 20% per year Estimated service life: 5 years Annual Operating Costs: $5000 in year 1, then increasing by $2000 per year thereafter Assuming i =10%, determine the economic service life of the challenger