C:/Users/pdaks/Downloads/Engineering%20Economics%20and%20Management%20(IHS%20241).pdf + CD | A " | | V v 2 1 8 16 2B A piece of machinery costs $7500 and has no salvage value after it is installed. The 05 manufacturer's warranty will pay the first year's maintenance and repair costs. In the second year, maintenance costs will be $900, and this item will increase on a $900 arithmetic gradient in subsequent years. Also, operating expenses for the machinery will be $500 in the first year and will increase on a $400 arithmetic gradient in the following years. If interest is 12%, what is the economic service life for this machine