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 $5\mathrm{.}4\%),$ AT&T preferred stock $($with a dividend yield of $5\mathrm{.}0\%),$ and state of Florida muni bonds $($which yield $4\%$ but are not taxable$).$ The federal 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 return on all three securities after paying federal corporate taxes. Round your answers to three decimal places.

After$-$tax rate of return on AT&T bond: $\%$

After$-$tax rate of return on AT&T preferred stock: $q,\%$

After$-$tax rate of return on Florida muni bonds: $\%$