If you're offline, you're not connected to anyone but your own console, so you can't play multiplayer.
No.
You can not play combat training offline.
You can only buy it online. But you can play the maps offline there after.
no
some of it and some not
Yes.
No
This is 2011 so you prolly know this and yes
You Cant Offline is maximum 2 Players except on Dead Ops Arcade you can play 1-4 players offline and online if anyone wants to talk about black ops 1 black ops 2 or world at war i know all the secrets hacks glitches aand everything of them contact me at andregoodarzi@hotmail.com
no you can play solo offline but you will need broadband iff you want to play multiplayer online.you can play split-screen offline though
you can play 4 player on zombies (black ops) but not offline you must play only nazi zombies i just found out sorry :)
Sadly, you can not. BUT you can play offline bots with 2 people.