Powel's Powerskis, Inc. uses a periodic inventory system.  The following transactions occurred during December 2012:

      Number of Units Cost per Unit
December 1 Beginning inventory 21 390
  8 Purchase 3 420
  15 Purchase 4 395
  20 Purchase 4 395
  22 Purchase 3 405

On December 31, there were 3 units remaining in ending inventory. 

a) Compute ending inventory and cost of goods sold using weighted average inventory.  Round final answers to 2 decimal places.  Do not round during intermediary steps.

Ending inventory: $

Cost of Goods Sold: $

b) Compute ending inventory and cost of goods sold using FIFO inventory costing.  Round final answers to 2 decimal places.  Do not round during intermediary steps.

Ending inventory: $

Cost of Goods Sold: $

c) Compute ending inventory and cost of goods sold using LIFO inventory costing.  Round final answers to 2 decimal places.  Do not round during intermediary steps.

Ending inventory: $

Cost of Goods Sold: $

d) What is the relationship among weighted average, FIFO, and LIFO ending inventory values?