Assume That Three Identical Units of Merchandise Were Purchased During

Assume that three identical units of merchandise were purchased during October,as follows:
$\begin{array}{|l|r|l|c|c|}\hline & & & \text { Units } & \text { Cost } \\\hline \text { October } & 5 & \text { Purchase } & 1 & \$ 5 \\\hline & 12 & \text { Purchase } & 1 & 13 \\\hline & 28 & \text { Purchase } & \underline{1} & 15 \\\hline \text { Total } & & & \underline{3} & \$ 33 \\\hline\end{array}$
Assume one unit is sold on October 31 for $28.Determine cost of merchandise sold,gross profit,and ending inventory under the LIFO method.