Crown Co. can produce two types of lamps, the Enlightner and Foglighter. The data on the two lamp models are as follows: Enlightner Foglighter Sales volume in units 520 390 Unit sales price $ 420 $ 440 Unit variable cost 300 270 Unit contribution margin $ 120 $ 170 It takes one machine hour to produce each product. Total fixed costs for the manufacture of both products are $91,000. Demand is high enough for either product to keep the plant operating at maximum capacity. Assuming that sales mix in terms of units remains constant, what is the breakeven point in total units