Those "two" missions is actually one mission called WMD.
14 i believe
5 Missions, about 6 hours.
There are 15 in the campaign mode
only in the campaign in one of the missions
you cant on demo
no
No, there will not be a demo.
There is no demo, anywhere in the world.
Conner there is a demo. whore
Not yet but I'm pretty sure that there will be. The Call of Duty Black Ops Demo has been released!
steam
No there is not