1) a) i) Explain briefly the difference between a free and a proprietary software. ii) Explain briefly what is meant by GNU/Linux". b) i) How does a normal user change password? ii) Give three ways in which a normal user can go to his/her home directory iii) What does the command: Is -ailtr do in the "/home/user1 directory", which contains the "Intro-Linux" sub-directory and several normal files? iv) List 3 commands which give information on the command "Is". v) List 3 commands which do not have a separate man page