You are running a crontab command and doesn't want the command to send an output to the crontab service, how can you handle it?

You can send all of the output from the command (STDOUT AND STDERR) to /dev/null - commandName 2>&1 >/dev/null

How can you list the arp cache table of the current machine?

You can use the command arp to control and view the arp table.

How can you eject your cdrom drive from the console?

In order to eject the cdrom drive, you can use the command eject.

You see a process "./myApplication" with PID 44556, how can you know where was the file executed from?

You can identify the path where the PID was executed by running pwdx 44556 and you will get the command executing path as an output.

You are doing an installation and want to record your commands and outputs for later review, how can you do that?

You can use the script application for this functionality - type script - a mysession.log and it will start recording your terminal to mysession.log, when you want to exit, type exit.