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Selling, general, and administrative expenses were $80,000; net sales were $390,000; interest expense was $16,000; research and development expenses were $34,000; net cash provided by operating activities was $42,000; income tax expense was $10,000; cost f goods sold was $220,000. Gross profit for the period was: Multiple Choice O $56,000 O $90,000 O $170,000 $390,000