Lista de fontes não pode ser linda no ubuntu 8.04

[wlsg]

Olá pessoal, meu gerenciador de pacotes synaptic e o adicionar e remover programas não abrem e apresentam o seguintes erros:
E: Tipo 'sudo' não é conhecido na linha 56 na lista de fontes /etc/apt/sources.list
E: A lista de fontes não pôde ser lida.
Configure as opções de repositórios para corrigir o problema.
E: _cache->open() failed, please report.
e no remover e adicionar programas o seguinte erro
Falha ao checar por aplicativos instalados e disponíveis

Esta  é uma falha grave de seu sistema gerenciador de programas. Por favor verifique se há pacotes mal instalados com a ferramenta synaptic, verifique as permissões e integridade do arquivo '/etc/apt/sources.list' e recarregue as informações do programa com o comando:'sudo apt-get update' e 'sudo apt-get install -f'.

como posso resolver esses problemas, se possível um passo a passo, pois sou iniciante no linux.

[agente100gelo]

Alt+F2 e execute:

Código Selecionar Expandir

gedit /etc/apt/sources.list

Copie o conteúdo do texto aqui.

[wlsg]

# deb cdrom:[Ubuntu 8.04 _Hardy Heron_ - Release i386 (20080423)]/ hardy main restricted
# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.

deb http://br.archive.ubuntu.com/ubuntu/ hardy main restricted
deb-src http://br.archive.ubuntu.com/ubuntu/ hardy main restricted

## Major bug fix updates produced after the final release of the
## distribution.
deb http://br.archive.ubuntu.com/ubuntu/ hardy-updates main restricted
deb-src http://br.archive.ubuntu.com/ubuntu/ hardy-updates main restricted

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## universe WILL NOT receive any review or updates from the Ubuntu security
## team.
deb http://br.archive.ubuntu.com/ubuntu/ hardy universe
deb-src http://br.archive.ubuntu.com/ubuntu/ hardy universe
deb http://br.archive.ubuntu.com/ubuntu/ hardy-updates universe
deb-src http://br.archive.ubuntu.com/ubuntu/ hardy-updates universe

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://br.archive.ubuntu.com/ubuntu/ hardy multiverse
deb-src http://br.archive.ubuntu.com/ubuntu/ hardy multiverse
deb http://br.archive.ubuntu.com/ubuntu/ hardy-updates multiverse
deb-src http://br.archive.ubuntu.com/ubuntu/ hardy-updates multiverse

## Uncomment the following two lines to add software from the 'backports'
## repository.
## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
# deb http://br.archive.ubuntu.com/ubuntu/ hardy-backports main restricted universe multiverse
# deb-src http://br.archive.ubuntu.com/ubuntu/ hardy-backports main restricted universe multiverse

## Uncomment the following two lines to add software from Canonical's
## 'partner' repository. This software is not part of Ubuntu, but is
## offered by Canonical and the respective vendors as a service to Ubuntu
## users.
# deb http://archive.canonical.com/ubuntu hardy partner
deb-src http://archive.canonical.com/ubuntu hardy partner

deb http://security.ubuntu.com/ubuntu hardy-security main restricted
deb-src http://security.ubuntu.com/ubuntu hardy-security main restricted
deb http://security.ubuntu.com/ubuntu hardy-security universe
deb-src http://security.ubuntu.com/ubuntu hardy-security universe
deb http://security.ubuntu.com/ubuntu hardy-security multiverse
deb-src http://security.ubuntu.com/ubuntu hardy-security multiverse
sudo tee -a /etc/apt/sources.list
sudo tee -a /etc/apt/sources.list
sudo tee -a /etc/apt/sources.list

[agente100gelo]

Alt+F2

Código Selecionar Expandir

gksudo gedit /etc/apt/sources.list

Remova as 3 últimas linhas e salve. Vá em Sistema > Administração > Gerenciador de Pacotes Synaptic e clique em recarregar.

[wlsg]

Obrigado agente100gelo,
segui as suas orientações e o problema foi 100% resolvido, quero deixar registrado o pronto atendimento e a maneira clara em que foi dada a solução, meu muito obrigado.

washington.