You cant. You need to play online against other players and you get promoted to new levels. You can, however, play combat training against computer players and get promoted the same way as you do online, but combat training and online are separate.
Black-ops will have an offline version of the multiplayer, with AI opposition. Also you will be able to level up as if you were online =)
You can but it doesn't count for online multiplayer.
In Black Ops multiplayer you unlock the AK-47 at level 38.
play multiplayer
No.
Commander Level 50.
of course on multiplayer
In Black Ops, you don't get an offline multiplayer account. It only shows your playercard from your online account. So the answer to your question is; you can't level up on your Black Ops splitscreen account because you don't get splitscreen accounts in Black Ops.
go to multiplayer, online, wager match, pick level (i would suggest ante up to start) then go to gun game
All you have to do is complete challenges, unlock camos, and of course get a lot of kills on multiplayer matches.
go to multiplayer and click on stats. this should say your level, prestige, kills, and deaths
Yes you do but only in Multiplayer when you level up