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A. history

B. envsetup

C. set

D. bashconf

E. setsh

A. Network interfaces may become active or inactive.

B. IP addresses may change.

C. The system's host name may change.

D. New name servers may be added to the resolver configuration.

E. The routing table may change.

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

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

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

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

A. It displays additional meta information from icon files ending in .ico.

B. It verifies that the root directory tree complies to all conventions from the Filesystem Hierarchy Standard (FHS).

C. It changes the mode of an inode in the ext4 file system.

D. It converts files from one character encoding to another.

E. It converts bitmap images from one format to another such as PNG to JPEG.

A. echo $ENV

B. env -a

C. set

D. env

A. text="olaf is home"

B. text=='olaf is home'

C. text=olaf\ is\ home

D. text=$olaf is home

E. $text='olaf is home'

A. Without additional configuration, all users may have user specific crontabs.

B. Without additional configuration, no users may have user specific crontabs.

C. When a user creates a user specific crontab the system administrator must approve it explicitly.

D. The cron daemon will refuse to start and report missing files in the system's logfile.

A. /usr/share/man

B. /var/pkg/man

C. /var/man

D. /usr/doc/

E. /opt/man