Carla Vista Department Store uses a perpetual inventory system. Data for product E$2-$D$2$ includes the following purchases.

On June $1,$ Carla Vista sold $24$ units, and on August $27,36$ more units.

$($a$1)$

Calculate the weighted$-$average unit cost for each sale. $($Round answers to $3$ decimal places, e$.$g$.5\mathrm{.}125.)$

June $1$ sale

$

Aug. $27$ sale

$