STU Corp. had $41,000,000 in revenues (sales), $12,600,000 in Costs of Goods Sold (COGS), $5,600,000 in SG\&A expenses, $4,800,000 in depreciation expenses, $3,400,000 in interest expenses, and $3,100,000 in tax expenses. The firm held $36,900,000 in total assets, of which $2,000,000 were in cash or equivalent, $4,800,000 were in accounts receivable, and $5,600,000 were in inventories. $24,600,000 of the $35,900,000 in total assets were in shareholder's equity. What was the firm's average tax rate? 21.23%19.85%18.23%22.92%