Which of the following statements is TRUE? Under variable costing, variable selling expenses are part of product costs. Under absorption costing, fixed selling expenses are part of product costs. Under absorption costing, fixed manufacturing overhead is part of period expenses. Under absorption costing, variable selling expenses are part of product costs. Under variable costing, fixed manufacturing overhead is part of period expenses. The contribution margin income statement differs from the gross margin income statement in which of the following ways? The contribution margin income statement is used for extemat reporting purpose. The effect of sales volume changes on proft is more apparent on the contribution margin income statement. The contribution income statement separates costs into product and period cost categories, Cost-volume-profit relationships can be analyzed more easily from the gross margin income statement. The gross margin income statement separates costs into fixed and variable components