What does the $ represent within the context of a shell command?

modprobe...

How do you redirect stderr to stdout?

To display contents of files on standard output, you could use the command:

How do you show all processes being run by a particular user?

'mv -f' will:

When archiving files, which command will preserve all file attributes including ACLs and SELinux security context?

What character class is equal to this set? [0-9]

Packages can be downloaded but not installed with yum or dnf by specifying which option?

Assume the variable myNumber holds a string consisting of 10 digits. What will this command output? echo \$myNumber | sed -e 's/^[[:digit:]][[:digit:]][[:digit:]]/(&)/g'

What does the /etc/nsswitch.conf file manage?