Use the following information to answer questions 4 through 7 : A product is sold for $75 each with unit cost of direct materials $20, direct labor $15, variable manufacturing overhead $12, and fixed manufacturing overhead $10. The volume produced and sold is 6,000 units. Variable and fixed marketing and administrative costs are $4 and $3, respectively. 4. Which of the following statements is correct? a. Prime cost is $35. b. Conversion cost is $37. c. Inventoriable cost is $57. d. All of the above. 5. What is the amount of cost of goods sold? a. $342,000 b. $201,500 c. $364,000 d. None of the above. 6. Which of the following statements is correct? a. Operating profit is $66,000. b. Gross margin is $108,000. c. Contribution margin is $144,000. d. All of the above