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7. rates of return of 5% and 6.4%, respectively. If the investor is in the 15% tax bracket, his after- tax rates of return on the municipal and corporate bonds would be, respectively your work A. 5% and 6.4% (2 points) An investor purchases one municipal bond and one corporate bond that pay . Show B. 5% and 5.44% C. 4.25% and 6.4% D. 5.75% and 5.44%