Andrea Cookie Company produced 5,000 cases of cookies this year. It sold 4,000 cases for $18 each. There were no beginning inventories. Variable manufacturing costs were $30,000, and fixed manufacturing expenses were $20,000. Selling and administrative expenses were $5,000, all fixed. a. Prepare income statements using the variable costing and absorption costing. b. Explain why net income under variable costing is different than net income under absorption costing when the same number of units was sold.