A.It is the process ID of the current shell.

B.It is the process ID of the last command which has been placed in the background.

C.It is the process ID of the echo command.

D.It is the process ID of the last command executed.

A.By selecting all affected lines using the shift and cursor keys before applying the command.

B.By issuing acommand such as :set repetition=4 which repeats every subsequent command 4 times.

C.By specifying the number right in front of a command such as 4l or 2yj.

D.By using the command :repeat followed by the number and the command.

A.It shows all mounted file systems that have been automatically mounted.

B.It ensures that all file systems listed in /etc/fstab are mounted regardless of their options.

C.It ensures that all file systems listed with the option noauto in /etc/fstab are mounted.

D.It opens an editor with root privileges and loads /etc/fstab for editing.

E.It ensures that all file systems listed with the option auto in /etc/fstab are mounted.

A.It is the root key by which all user SSH keys must be signed.

B.It must be sent by any SSH client in addition to a user key in order to identify the client's host.

C.It is used by system services like cron, syslog or a backup job to automatically connect to remote hosts.

D.It provides the server's identity information to connecting SSH clients.

E.It authenticates any user that logs into a remote machine from the key's host.

A.It is the exit value of the echo command.

B.It is the process ID of the current shell.

C.It is the exit value of the command executed immediately before echo.

D.It is the process ID of the echo command.