O unfavorable direct materials ethiciency variante QUESTION 19 Waterproof Roofing Company has provided the following information: Sales revenue $779,000 Variable costs 506,000 Fixed costs 216,000 Which of the following statements is true, if the sales volume increases by 10%? o Operating income will increase by $50,600. O Contribution margin will increase by $77,900. O Fixed expenses will increase by $21,600. O Operating income will increase by $27,300. QUESTION 20 I mit demure the contribution margin per unit