Two types of machine tools are available for performing a particular job in a certain manufacturing firm. The estimated costs and salvage values are summarized in the following table:

	Machine A	Machine B
First Cost	$30,000	$40,000
O&M costs/year	$3,000	$2,500
Service Life	6 years	8 years
Salvage Value	$6,000	$4,000
Depreciation Method	MACRS (GDS)	MACRS (GDS)
	^^(straight-line method)
Recovery Period	5 years	5 years

The effective state and federal tax rate is 50% and the capital-gains rate is 35%. Make your comparison after income taxes, using an MARR of 10% and indicate the study period.