Answer:
Montesquieu called the idea of dividing government power into three branches the "separation of powers." He thought it most important to create separate branches of government with equal but different powers. That way, the government would avoid placing too much power with one individual or group of individuals.
There were three Nebuchadnezzar's who reigned. Assuming that you are talking about Nebuchadnezzar I, he reigned during 1125 - 1104 BC.
The following are correct:
A moat filled with water from the Euphrates River surrounded the city.
Walls around the city provided protection from enemies.