Once you redeem your mutliplayer code, You may not and you are unable to un-redeem it. The code you entered will not be able to be used ever again. Sorry for the bad news.
You have to be 13 years old to play on the multiplayer for Battlefield 3.
Yes, the support man in battlefield 3 has unlimited ammo for him and all of his teammates.
Nope, it's only an expansion pack for multiplayer.
Yes.
Battlefield 3 does have Co-op mode, you can also unlock weapons for use in Multiplayer from playing Co-op.
you must be in the assault group. keep on playing multiplayer online and you will sometime unlock it through the assault kit.
Uncharted 3 is a must have if you have a PS3. Popular multiplayer games are MW3 and Battlefield but none compares to UC3. But in my opinion battlefield is the worst out of these 3.
Not if you've bought the game it gives you a code for it in the box.
Your character repeatedly swears in multiplayer and there is plenty of swearing in single player.
Ya
You can't. The multiplayer disc is the only one that allows you to connect to the network. Campaign disc is purely the campaign.
In Battlefield 3, there are a total of twelve single-player campaign missions, six two-player co-operative missions and nine multiplayer maps; an addition of four multiplayer maps in the downloadable content pack Back to Karkand.