Continuing the previous exercise, what would the cost per buyer be if awareness was only $50\%?($Retain other assumptions from d$.$ above and change level of prospects aware.$)$

multiple choice $5$

$$8\mathrm{.}65$

$$10\mathrm{.}42$

$$13\mathrm{.}68$

$$14\mathrm{.}59$

$$17\mathrm{.}06$