You logged in as user tuxl, but now you want to switch users to tux2 with tux2's environment. How would you do this?

The `su tux2` command switches to the user `tux2` but retains the environment of the original user (`tux1`), which does not provide `tux2`'s environment.

`su -e` is not a standard or correct option for establishing a new user's environment; `-e` (or `--preserve-environment`) typically preserves the *current* user's environment.

The `su - tux2` command is the correct way to switch to user `tux2` and load their complete environment. The hyphen (`-`) after `su` simulates a full login, sourcing the target user's profile and setting up their home directory, PATH, and other environment variables appropriately.

The `su -m` (or `--preserve-environment`) option prevents `su` from setting up the target user's environment, keeping the original user's environment, which is not desired in this scenario.

`su -f` (or `--fast`) passes the `-f` flag to the shell, which typically prevents it from sourcing startup files, thus not loading the target user's full environment.