Question:
In problem 1, what is the ``membership'' of a team?
Answer:
This question was designed by a soccer fanatic, so I'm
guessing that it is the league in which the team participates.
Apparently this is a big deal in European soccer, where teams are moved
to better or worse leagues, depending on how they did the previous year.
Question:
What is ``mixing''? What is a ``version'' of a song?
Answer:
Actually, it doesn't matter. All you need to know is given by the ODL in
Problem 2. Songs are mixed by DJ's, and versions is a symmetric relation
on songs.
I would imagine that two songs are versions of each other if they have
the same basic melody and words.
The process of mixing is a combining of electronic signals, usually
from instruments or microphones. Perhaps someone who is more into music
than I am can give me more details, which I will post here.
But again, you can answer the questions without understanding the
underlying electronics.