Variable Costing Ferguson Company has the following information for March: Sales $680,000 Variable cost of goods sold 312,800 Fixed manufacturing costs 108,800 Variable selling and administrative expenses 61,200 Fixed selling and administrative expenses 47,600 Determine the following for Ferguson Company for the month of March: a. Manufacturing margin $fill in the blank 1 b. Contribution margin $fill in the blank 2 c. Income from operations $fill in the blank 3