A firm using FIFO had a beginning inventory of $48,000, an ending inventory of $56,000, and a pretax income of $400,000. If it had used LIFO, its beginning inventory would have been $20,000, its ending inventory would have been $16,000, and its pretax income would have been:

$374,000

$388,000

$396,000

$404,000

please show your work clearly!!!