Q3: The following table gives the operation cost, maintenance cost and salvage value at the end of every year of a machine whose purchase value is 25,000$. Find the economic life of the machine assuming interest rate, i = 15%. End of Year (n) Cost operation at the end of year ($) Maintenance cost at the end of year ($) Salvage value ate end of the year ($) 1 3000 300 9000 2 4000 400 8000 3 5000 500 7000 4 6000 600 6000 5 7000 700 5000 9 8000 800 4000 7 9000 900 3000 8 10000 1000 2000 9 11000 1100 1000 10 12000 1200 500