$[$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.