copy right questions

In Digital Literacy today we are looking into copy right issues. In CASE study 1 we had to listen to George Harrison's song ''My Sweet Lord'' and compare it to Ronald Mack's song ''He's So Fine''. I could'nt hear any similarity but then musically I am un trained I presume the copyright experts must have been able to prove it for George Harrison to be found guilty.In CASE study 2 the movie ''12 Monkeys'' used a chair on a verticle rail which looked very similar to a pencil drawing by Lebbeus Woods.CASE study 3 Keir Smith made a video dealing with copyright exceptions and fair use .It is a powerful statement but I think it is breaching copyright laws or is it creative use? Below is a beautiful image by Frida Kahlo which I down loddered[with an enormous amount of help from Max] from the official website of Frida Kahlo. I have listed it's title and where it came from so that I am covered by copyright as requested from our work book.