Suppose the beta of Exxon$-$Mobil is $0\mathrm{.}75,$ the risk$-$free rate is $5\%,$ and the expected market rate of return is $15\%.$ Calculate the expected rate of return on Exxon$-$Mobil.

$12\mathrm{.}5\%$

$10\mathrm{.}5\%$

$13\mathrm{.}1\%$

$6\mathrm{.}5\%$