Mowbots manager of environmental engineering has identified a need for new equipment to remove contaminants from a process exhaust. She has identified four possible pieces of equipment, each of which meet the technical requirements, but have different operating cost parameters. Using incremental rate of return analysis, choose the most cost effective solution.

	Alphaclean	Betaclean	Envirogamm	Cycledelta
Up front cost	$225,000	$460,000	$375,000	$510,000
Annual operation cost	$80,000	$45,000	$65,000	$25,000
Residual (salvage)	$50,000	$75,000	$60,000	$60,000
Project life (years)	20	20	20	20
MARR	18%	18%	18%	18%