please help with 1 2 and 3

LG's Appliances uses the periodic inventory system. Details regarding the inventory of appliances on January 1, purchases invoices during the year, and the inventory count on December 31 are summarized as follows: 1. Determine the cost of the inventory on December 31 by the first-in, first-out method. Present data in columnar form, using the following headings: If the inventory of a particular model comprises one entire purchase plus a portion of another purchase acquired at a different unit cost, use a separate line for each purchase. 2. Determine the cost of the inventory on December 31 by the last-in, first-out method, following the procedures indicated in (1). 3. Determine the cost of the inventory on December 31 by the weighted average cost method, using the columnar headings indicated in (1)