An electronics manufacturer is considering the purchase of one of two types of laser trimming devices. The sales forecast indicated that at least 8,000 units will be sold per year. Device A will increase the annual fixed cost of the plant by $20,000 and will reduce variable cost by $5.60 per unit. Device B will increase the annual fixed cost by $5,000 and will reduce variable cost by $3.60 per unit. If variable costs are now $20 per unit produced, which device should be purchased?