\begin{tabular}{rlrcc} & & & \multicolumn{1}{c}{ Cost } & Sales \\ May 1 & Beginning inventory & 90 units & $36,000 & \\ 5 & Sale & 60 units & & $31,200 \\ 9 & Purchase & 30 units & $13,200 & \\ 13 & Purchase & 120 units & $57,600 & \\ 24 & Sale & 120 units & & $67,200 \\ 27 & Sale & 30 units & & $19,200 \\ 30 & Purchase & 45 units & $23,760 & \end{tabular} Cost of goods sold \$ Gross margin $ Endinginventory \$