21. BE 21.01.ALGO (Algorithmic) Variable Costing Norwood Company has the following information for July: Sales $530,000 Variable cost of goods sold 254,400 Fixed manufacturing costs 84,800 Variable selling and administrative expenses 58,300 Fixed selling and administrative expenses 37,100 Determine the following for Norwood Company for the month of July: a. Manufacturing margin $ b. Contribution margin $ c. Operating income $