Selling, general, and administrative expenses were $67,000; net sales were $304,500; interest expense was $7,200, research and development expenses were $31,900; net cash provided by operating activities was $80,200; income tax expense was $7,700, cost of goods sold was $167,200. Required: a. Calculate operating income for the period. Operating expenses. b. Calculate net income for the period. Interest expense Income tax expense