$5.$ A $$100$ par preferred stock pays a $13\%$ dividend semiannually.

a$.$ If comparable investments yield $11\%,$ what is the price of the preferred stock?

b$.$ If comparable investments yield $15\%,$ what is the price of the preferred stock?

c$.$ If the firm must retire the preferred stock after $20$ years, how does this affect the price of the

stock in $($a$)$ and $($b$)?$

d$.$ Compare your answers to parts $($a$)$ and $($b$).$ What do these differences imply?