Dec. 31. Jan. 1 Raw Materials Inventory Work in Process Finished Goods $330 $340 $350 $340 $190 $370 $1,130 Direct materials used Total Manufacturing costs charged to production of which $855 was manufacturing overhead $3,340 Selling and administrative expenses Sales revenue $2,460 $6,390 Required: (1) What is the cost of materials purchased? (2) What is the cost of goods sold? (3) What is gross profit? (4) What is net profit