The expected return for Stock Z is $30$ percent. If we know the following information about Stock Z$,$ then what return will it produce i the Lukewarm state of the world?

$\backslash$table$[[,$Return,Probability$],[$Poor$,0\mathrm{.}2,0\mathrm{.}25],[$Lukewarm$,?,0\mathrm{.}5],[$Dynamite$,0\mathrm{.}4,0\mathrm{.}25]]$

$30\%$

$50\%$

$40\%$

$20\%$