I don't understand this. Please thoroughly explain. Im trying to complete with paper and pencil. Please fully explain how I show calculate not understanding how. Trying to carry all calculations to two decimal places to reduce rounding error, especially in multi$-$step problems.Integrative Case $4$ Enviro Plastics Company

Since its inception, Enviro Plastics Company has been revolutionizing plastic and trying to do its

part to save the environment. Enviro's founder, Marion Cosby, developed a biodegradable plastic

that her company is marketing to manufacturing companies throughout the southeastern United

States. After operating as a private company for six years, Enviro went public in $2015$ and is listed

on the Nasdaq stock exchange.

As the chief financial officer of a young company with lots of investment opportunities, Enviro's

CFO closely monitors the firm's cost of capital. The CFO keeps tabs on each of the individual costs

of Enviro's three main financing sources: long$-$term debt, preferred stock and common stock. The

target capital structure for Enviro is given by the weights in the following table:

At the present time, Enviro can raise debt by selling $20-$year bonds with a $$1,000$ par value and a

$10\mathrm{.}5\%$ annual coupon interest rate. Enviro's corporate tax rate is $21\%,$ and its bonds generally

require an average discount of $$45$ per bond and flotation costs of $$32$ per bond when being sold.

Enviro's outstanding preferred stock pays a $9\%$ dividend and has a $$95-$per$-$share par value. The

cost of issuing and selling additional preferred stock is expected to be $$7$ per share. Because Enviro

is a young firm that requires lots of cash to grow, it does not currently pay a dividend to common

stockholders. To track the cost of common stock the CFO uses the capital asset pricing model

$($CAPM$).$ The CFO and the firm's investment advisors believe that the appropriate risk$-$free rate is

$4\%$ and that the market's expected return equals $13\%.$ Using data from $2015$ through $2021,$ Enviro's

CFO estimates the firm's beta to be $1\mathrm{.}3.$

Although Enviro's current target capital structure includes $20\%$ preferred stock, the company is

considering using debt financing to retire the outstanding preferred stock, thus shifting their target

capital structure to $50\%$ long$-$term debt and $50\%$ common stock. If Enviro shifts its capital mix

from preferred stock to debt, its financial advisors expect its beta to increase to $1\mathrm{.}5.$

To Do

a$.$ Calculate Enviro's current after$-$tax cost of long$-$term debt.

b$.$ Calculate Enviro's current cost of preferred stock.

c$.$ Calculate Enviro's current cost of common stock.

d$.$ Calculate Enviro's current weighted average cost capital $($WACC$).$

e$.(1)$ Assuming that the cost of debt financing does not change, what effect would a shift to a

more highly leveraged capital structure consisting of $50\%$ long$-$term debt, $0\%$ preferred

stock, and $50\%$ common stock have on the risk premium for Enviro's common stock?

$(2)$ What would be Enviro's new cost of common equity?

$(3)$ What would be Enviro's new weighted average cost of capital $($WACC$)?$

$(4)$ Which capital structure$-$the original one or this one$-$seems better? Why?