COGS ACCOUNT & Deffred COGS ACCOUNT

 DEAR all hope you all fine ... i want to know few things from you as;

1) While defining an Inventory Org  i have enter the COGS & Deffred COGS account .. now i want to ask u that either these two account should be same or diffrent i mean either each have the same CCID or it could be Different ??
2) Is it possible that two inventory have diffrent COGS & Deffered COGS Accounts ??
3) While Defining an Inventory Org we require to give the COGS account in the Costing tab ..... therfore i need to know either this would be the same account as i had defined in the Inventory Org or not ????