Can anyone breakdown perpetual inventory systems and FIFO for this kind of problem? I don't understand.

Gonzalez Company had the following information for the year ending December 31: Units Unit Cost Beginning inventory 340 $45 Purchase: April 6 460 44 Sale: May 4 550 Purchase: July 19 590 43 Sale: September 9 380 Purchase: October 10 100 32 Gonzalez uses the perpetual inventory system and the FIFO method. Required: Using FIFO (a) Compute the cost of ending inventory. (b) Compute the cost of goods sold for the year. Cost of ending inventory Cost of goods sold $0 X 5