The Inventory Records of ZUP Indicate the Following Regarding Its

The inventory records of ZUP indicate the following regarding its best-selling product for the month of January:
$$\begin{array} { | l | r | r | } \hline & \text { Units } & \text { Unit cost } \\\hline \text { Opening inventory } & 6,000 & \$ 4,00 \\\hline \text { Purchase 1 } & 4,000 & 3.70 \\\hline \text { Sale 1 } & ( 3,600 ) & \\\hline \text { Purchase 2 } & 8,000 & 2.80 \\\hline \text { Sale 2 } & \underline { ( 5,000 } \\\hline \text { Ending inventory } & \underline { 9,400 } \\\hline\end{array}$$ Required:
Calculate the dollar amount of ending inventory and cost of goods sold under each of the following cost flow assumptions:
a. Weighted-average cost, periodic inventory.
b. First-in, first-out (FIFO), perpetual inventory.
c. Weighted-average cost, perpetual inventory.