FIFO, LIFO, and Weighted Average Effect

Under rising prices, which inventory method reports the highest ending inventory?

FIFO.

What is the trade-off between FIFO and LIFO under inflation?

FIFO improves balance sheet realism; LIFO improves income statement realism.

Under rising prices, which inventory method reports the highest $COGS$?

LIFO.

Why does FIFO produce higher net income than LIFO during inflation?

Older, cheaper costs flow to $COGS$, so gross profit is higher.