0 . Consider the following comments about absorption - and variable - costing income statements 1 . A variable - costing income statement discloses a firm's contribution margin 1 . Cost of goods sold on an absorption - costing income statement includes fixed costs III . The amount of variable selling and administrative cost is the same on absorption - and variable - costing income statements Which of the above statements is ( are ) true ? only I and I I only 1 , and Ill