Can you please explain the math used to get these answers?

Estimated Income Statements, using Absorption and Variable Costing Prior to the first month of operations ending July 31, 2014, Muzenski Industries Inc. estimated the following operating results: $2,160,000 Sales (28,800x$75) Manufacturing costs (28,800 units) 1,324,800 Direct materials Direct labor 16,800 Variable factory overhead 144,000 216,000 Fixed factory overhead Fixed selling and administrative expenses 29,400 Variable selling and administrative expenses 35,500 The company is evaluating a proposal to manufacture 36,000 units instead of 28,800 units, thus creating an ending inventory of ,200 units. Manufacturing the additional unit s will not change sales, unit variable factory overhead costs, total fixed factory overhea cost, or total selling and administrative expenses Hint(s) Hide Prepare an estimated income statement, comparing operating results if 28,800 and 36,000 units are manufactured in the absorption costing format. Muzenski Industries Inc. Absorption costing Income Statement Forthe Month Ending July 31 2014 28,800 Units Manufactured 36,000 Units Manufactured Coes 2160000 2160000 Cost of goods sold Cost of goods manufactured 2001600 2448000 489600 Less inventory, July 31 2001600 1958400 Cost of goods sold 158400 201600 Gross profit 64900 64900 Selling and administrative expe 93500 136700 Income from operations