This isn't a command - it appears to be an option (switch) on a different command.
A user may switch their identities when logged in using the 'su' command. On some systems the 'su' command may be restricted.
Electronic Circuit
There are many variations of the useradd command; most standard installations may not have this switch. Please identify which Unix system you are talking about.
== ==
There is not switch called "if". We generally use "if" statement in batch programming in DOS.
Time Switch, Command Switch, Electronic Circuit, Victim Operated
True
You can run "dir /?" command.
It allows you to switch users.
Running the ping command with -n "count" is the number of echo request to send.
False