There are four methods for inventory costing: LIFO, FIFO, weighted average and specific identification. What are the differences between each method?...

There are four methods for inventory costing: LIFO, FIFO, weighted average and specific identification. What are the differences between each method? How does each method affect the balance sheet and the income statement? What do I mean when I say that inventory costing methods are not related to the physical flow of inventory? Please give an example.