Problem $08\mathrm{.}045-$ Evaluation of two options based on useful life

Holly Farms is considering two environmental chambers to accomplish detailed laboratory confirmations of online bacteria tests in chicken meat for the presence of E$.$ coli $0157$:H$7$ and Listeria monocytogenes. There is some uncertainty about how long the D$103$ chamber will be useful. A realistic estimate is $3$ years, but pessimistic and optimistic estimates of $2$ years and $6$ years, respectively, are also reasonable. The estimated salvage value will remain the same. Using an interest rate of $10\%$ per year, determine if any of the D$103$ estimates would result in a lower cost than that of the $490$ G chamber for a $6-$year planning period.

$\backslash$table$[[,$Chamber D$103,$Chamber $490$G$],[$Installed cost$,P,$$$,-400,000,-280,000$