12. Page 92: Corporate After-Tax Yield - The Shrieves Corporation has $10,000 that it plans to invest in marketable securities. It is choosing among AT\&T bonds (which yield 6.6\%), AT\&T preferred stock (with a divi-dend yield of 6.0% ), and state of Florida muni bonds (which yield 5% but are not taxable). The fecleral tax rate is 21% (ignore any possible state corporate taxes). Recall that 50% of dividends received are tax exempt. Find the after-tax rates of retum on all three securi-ties after paying federal corporate taxes