Which of the following statements are true? I. Contribution margin and gross margin mean the same thing. II. The contribution format income statement is used as an internal planning and decision-making tool. Its emphasis on cost behavior aids cost-volume-profit analysis, management performance appraisals, and budgeting. III. A contribution format income statement separates costs into fixed and variable categories, first deducting variable expenses from sales to obtain the contribution margin. Multiple Choice Both statements II and III are true. Only statement I is true. All of the statements are true. None of the statements are true