Suppose that your window manager has exited and you cannot get focus in a window to type a command to bring up a new one (and that you have no root menu button that starts a new one). Explain how you might still be able to use copy-and-paste with your existing windows to execute a command.

What will be an ideal response?

You can select characters from other windows you may have open to “build” a command to restart
your appropriate window manager program (e.g., gnome-wm, kwm, mwm, fvwm, etc.) by
selecting, copying, and pasting, character by character if necessary, into a command window.
Then copy and paste a carriage return (the space at the end of a line to the next line) and the
window manager will be started (running in that window).