It doesn't answer these questions but provides a feast of food for thought.
Here's a quote:
When I asked to use a single line by songwriter Joe Henry, for example, his record label's parent company demanded $150 for every 7,500 copies of my book. Assuming I sell enough books to earn back my modest advance, this amounts to roughly 1.5% of my earnings, all for quoting eight words from one of Mr. Henry's songs.
I love Joe Henry, but the price was too high. I replaced him with Shakespeare, whose work (depending on which edition you use) is in the public domain.
That was then — July 9, 2010. Now, let us return to our subject. As a YouTube videographer (www.YouTube.com/julesolder), I find it evermore vexatious. Do I ask for permission to use a background song from a 1936 movie? If MGM or UA says, “We have to consult our legal department,” I won't get the video out for an eternity. If they say, “Sure, but you have to pay for it,” I won't get it out at all.