Please answer both requirements (a and b)

The following information is available for Robstown Corporation for 20Y8 Inventories Materials Work in process Finished goods January 1 $78,900 109,800 113,750 December 31 $93,850 95,500 109,000 Advertising expense Depreciation expense-office equipment Depreciation expense-factory equipment Direct labor Heat, light, and power-factory Indirect labor Materials purchased December 31 $68,200 21,000 14,780 186,800 5,650 24,700 123,600