A. What is the use of a shell? B. Is there any difference between the shell that you see on your PC versus that you see on the snowball server upon login. If yes, what are they? Provide screenshots for examples. C. What are the elements in a computer (software and hardware) that enable the understanding and interpretation of a C program? D. The "printf()" C command is used for printing anything on the screen. In bash we use the command "echo ". What is the difference (if any) in terms of how the computer interprets and executes these commands? E. What do these shell commands do? "ssh", "scp" and "wget". Describe briefly using an example that you have executed using the snowball server.