Here are my thoughts and responses as to what I come to know for these civilizations' achievements. I even checked my World History notes from last year...
1. Egyptians
2. Sumerians
3. Phoenicians
4. -This is debatable... We could argue early caveman or Sumerians made it, depends on what resource, textbook, or class material you are deriving this from. Maybe Hebrew because they developed Monotheism, belief in one deity.
5. Hittites
6. This is very difficult to elaborate on. Many civilizations had very strikingly similar achievements and reviewing my notes, I can't find anything to give an absolute civilization responsible for this. You'll have to guess.
7. Babylonian?
Sorry I couldn't help with #4, 6, and 7 that well. It's very difficult to answer.
They were created to finance endeavors that were far too expensive for individuals to invest in and even governments to fund.
hope that helps!
I think it should be thick and it should be aluminum because aluminum is a good conductor... and i don't think it matters if its above ground or underground.. because if u look outside now most of the wires are above ground but they are starting to make them underground now.. so if u have to pick one just say above ground