I am trying to follow these instructions to permit new updates of an opensource GIS software program to take place on my Ubuntu: http://qgis.org/en/site/forusers/alldownloads.html#ubuntu
I used nano to add the following lines:
sudo apt-get update sudo apt-get install qgis python-qgis sudo apt-get install qgis-plugin-grass
only to discover that sudo is "not known" and caused an error. When I tried to reopen the sources.list file I get a blank screen in the terminal (below). Please, please advise.