Suppose Westerfield Co$.$ has the following financial information:

Debt: $900,000$ bonds outstanding with a face value of $$1,000.$ The bonds currently trade at $85\%$ of par and have $12$ years to maturity. The coupon rate equals $7\%,$ and the bonds make semiannual interest payments.

Preferred stock: $600,000$ shares of preferred stock outstanding; currently trading for $$108$ per share, paying a dividend of $$9$ annually.

Common stock: $25,000,000$ shares of common stock outstanding; currently trading for $$185$ per share. Beta equals $1\mathrm{.}22.$

Market and firm information: The expected return on the market is $9\%,$ the risk$-$free rate is $5\%,$ and the tax rate is $21\%.$

a$.)$ Calculate the after$-$tax cost of debt. $($Enter percentages as decimals and round to $4$ decimals$)$

b$.)$ Calculate the cost of preferred stock. $($Enter percentages as decimals and round to $4$ decimals$)$

c$.)$ Calculate the cost of common stock. $($Enter percentages as decimals and round to $4$ decimals$)$

d$.)$ Calculate the weighted average cost of capital. $($Enter percentages as decimals and round to $4$ decimals$)$