how to get FIFO and LIFO then gross profit

[The following information applies to the questions displayed below.] Tree Seedlings has the following current-year purchases and sales for its only product. The company uses a periodic inventory system. a. Determine the costs assigned to ending inventory and to cost of goods sold using FIFO. b. Determine the costs assigned to ending inventory and to cost of goods sold using LIFO. c. Compute the gross profit for each method. Determine the costs assigned to ending inventory and to cost of goods sc \begin{tabular}{|l|l|l|} \hline Periodic Inventory System & Ending Inventory & CostofGoodsSold \\ \hline LIFO & & \\ \hline \end{tabular} \begin{tabular}{|l|l|l|l|} \hline & \multicolumn{2}{|c|}{ FIFO } & \multicolumn{2}{c|}{ LIFO } \\ \hline & & & \\ \hline Gross profit & & & \\ \hline \end{tabular}