A user created a report.sh script in the home directory.
When executing /home/user/report.sh the user receives the following error message:

The user executes the following diagnostic commands:

Which of the following is causing the error message?

An administrator wants to know the amount of memory installed on a Linux server. Which of the following commands can be used to accomplish this task?

A Linux administrator has installed a web application firewall in front of a web server running on HTTP port 8080 and successfully started the HTTP server. However, after opening the application URL in an Internet browser, the administrator discovered that the application does not work. The administrator performed the following diagnostic steps:
Output of sysctl -a command:

Output of iptables -L command:

Output of netstat -nltop | grep "8080":

Which of the following is the NEXT step the administrator should perform to permanently fix the issue at the kernel level?

Which of the following commands would show the default printer on a Linux system?

An administrator wants to add a user named comptia to the system administrators group. Which of the following commands will accomplish this task?