computer video

https://www.youtube.com/watch?v=tu4MOCJrRWk

watch the video and answer the following questions (After watching!)

1. How to use Nmap in its basic form to scan for all computers on the class C subnet of 192.168.27.0?  Specify the exact Nmap command to achieve this.
2. How do you scan a host for only the following ports: 22,23,80,8080  ?
3. How did the presenter create a file of his scan results ?
4. Specify the exact Linux distro the presenter using in this video! And how did he delete a file ?
5. In short, what did the presenter meant by “Grepable” output ?