On January $1,2015,$ a certain corporation was trading at $$60$ per share. At the end of December of the same year, the stock closed at $$40.$ The firm paid a $$2\mathrm{.}00$ dividend on each share during the year.

a$.$ What was the rate of return that shareholders earned in the year?

b$.$ The yield on long$-$term US Treasuries at the beginning of $2015$ was $5\%.$ Investors a $5\%$ risk premium $($rM $$ rf$)$ for this stock. What is your required rate of return $($the beta return$)?$ Show all your hand$-$written calculations here $($clearly$,$ please$)$