Do you need permission from the copyright owner of Avatar to post a parody? In other words, can you use a scene from the movie and have the characters make fun of the story-line? See https://web.law.duke.edu/cspd/comics/ and/or herehttps://fairuse.stanford.edu/overview/fair-use/what-is-fair-use/ for some ideas on this question.

What does the owner of a phrase, sound, name, or logo, need to do to make a trademark (hint: register is not the answer)? See https://cyber.harvard.edu/metaschool/fisher/domain/tm.htm

If you scan a photo illustration of the Mona Lisa from an Art Magazine is it infringement to use it as a CD cover without permission? If so, on whose rights are you are infringing? (hint: what kind of photo?)