I can answer more than half of them! This makes me happy because I am a relatively new *nix user. I even know the answer of "What is the maximum length of CAT6?" which is actually very easy to look up. So the easy ones according to me are these: 1-4, 6-9, 11, 14, 17 (provided that you change "red hat" with "debian" in some of the questions).
I don't know those things about OSI and layers. But I bet I can answer one or two after reading this: http://en.wikipedia.org/wiki/OSI_model
I am a bit ashamed that I don't know the answers of 5 & 15. Can anyone answer them:
5. Give an example of a set of shell commands to tell how many times “bob” has logged on to the system this month.
15. Show an example of using telnet to learn the headers of an http server.