deb http://us.archive.ubuntu.com/ubuntu/ precise main universe restricted multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ precise main universe restricted multiverse

deb http://security.ubuntu.com/ubuntu precise-security main universe restricted multiverse
deb-src http://security.ubuntu.com/ubuntu precise-security main universe restricted multiverse

deb http://us.archive.ubuntu.com/ubuntu/ precise-updates main universe restricted multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ precise-updates main universe restricted multiverse