the answer isnt 6.46% or 5.45% please help

Required: Find the after-tax return to a corporation that buys a share of preferred stock at $58, sells it at year-end at $58, and receives a $4 year-end dividend. The firm is in the 21% tax bracket. (Round your answer to 2 decimal places.) Hint: Corporations may exclude 50% of dividends received from preferred stocks in calculating their taxable income