10 points A company earns gross margin of 30% on all sales. The gross profit amounts to $21,000. How much are cost of sales and revenue? Cost of sales =$70,000; Revenue =$91,000 Cost of sales =$70,000; Revenue =$100,000 Cost of sales =$49,000; Revenue =$56,000 Cost of sales =$49,000; Revenue =$70,000