Mogul Processing maintains its internal inventory records using average cost under a perpetual inventory system. The following information relates to its inventory during the year:

January $1$ Beginning inventory$-91,200$ units.

February $14$ Purchased $136,800$ units for $$4\mathrm{.}50$ each.

March $5$ Sold $171,000$ units for $$14\mathrm{.}00$ each.

August $27$ Purchased $57,000$ units for $$4\mathrm{.}80$ each.

September $12$ Sold $68,400$ units for $$14\mathrm{.}00$ each.

November $15$ Purchased $79,800$ units for $$4\mathrm{.}90$ each.

December $31$ Ending inventory $125,400$ units.

Required:

Determine the amount Mogul would calculate internally for ending inventory and cost of goods sold using average cost under a perpetual inventory system. Beginning inventory under average cost was $91,200$ units with a average cost of $$4\mathrm{.}25$ each.

Determine the amount Mogul would report externally for ending inventory and cost of goods sold using last$-$in$,$ first$-$out $($LIFO$)$ under a periodic inventory system. Beginning inventory under LIFO was $91,200$ units with a cost of $$4\mathrm{.}00$ each.

Determine the amount Mogul would report for its LIFO reserve at the end of the year.

Record the year$-$end adjusting entry for the LIFO reserve. The balance of the LIFO reserve at the beginning of the year was $$22,800.$