PWD = current working directory.
BASH = Full path name used to execute the current instance of bash.
Nothing much to say here. No thinking, or logic needed. You simply need to know how to access the manual pages or other reference works for your command shell.
You may wish to familiarize yourself with the "man" command. At the command line, type:
man man
And read what comes up. If the "man" command isn't installed on your system, please install it if you have the ability, or ask your instructor why it isn't installed.
