All Rite Manufacturing reported the following: Revenue $450,000 Beginning inventory of direct materials, January 1, 2015 30,000 Purchases of direct materials 153,000 Ending inventory of direct materials, December 31, 201518,000 Direct manufacturing labor 26,000 Indirect manufacturing costs 42,000 Beginning inventory of finished goods, January 1, 2015 47,000 Cost of goods manufactured 233,000 Ending inventory of finished goods, December 31, 2015 41,000 Operating costs 157,000 What is All Rite's gross margin (or gross profit)? : a. $54,000 b. $60,000 c. $217,000 d. $211,000