A factory asset has a first cost of $100,000, annual costs $15,000 the first year and increasing by 7.5% per year, and a salvage (market) value that decreases by 20% per year over its 5-year life. The minimum cost economics life of the asset is what value? Interest is 10%.

a) 2 years b) 3 years c) 4 years d) 5 years

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