Product Total A B C Sales.......... $100,000 $50,000 $20,000 $ 30,000 Variable expenses .... 60,000 30,000 10,000 20,000 Contribution margin 40,000 20,000 10.000 10.000 Fixed expenses: 5,000 2,500 1,000 1,500 Depreciation 6,000 3,000 1,200 1,800 Utilities ..common 4,000 2,000 500 1,500 Supervisors' salaries ..... 5,000 1,500 500 3,000 Maintenance ......!!! 3,000 1,500 600 900 Administrative expenses..... 10,000 3,000 2,000 5,000 Total fixed expenses...... 33,000 13,500 5.800 13,700 Net operating income .until $ 7.000 $ 6.500 $ 4.200 $( 3,700)