Phillips Company manufactures air-conditioning units for commercial buildings and has noticed considerable variation in shipping expenses from month to month as per the data below: Month January February March April May June July Total Units Shipping Shipped Expense 4 $ 2,200 4 $ 3,100 5 $ 2,600 $1,500 3 $ 2,200 6 $3,000 8 $ 3,600 N es 10. Given the facts in part 38, if total fixed costs (excluding shipping) are $3,000 per month, estimate operating income for August if seven air conditioners are produced and sold. Month January February March April May June July Total Units Shipping Shipped Expense 4 $2,280 4 $3,1ee 5 $ 2,600 2 $1,500 3 $2,200 6 $3,000 8 $3,6ee 8. If the air conditioners have an average sales price of $5,000, variable direct manufacturing costs are $2,500 per unit, variable manufacturing overhead costs are $500 per unit, and variable selling and administration costs (excluding shipping) are $200 per unit, what is the contribution margin per unit