Two important aspects of the U.S. Constitution; federalism<span> and the separation of powers; represent, in part, the framers' efforts to divide governmental </span>power. Federalism limits<span> government by creating two sovereign powers; the </span>national <span>government and state government; thereby restraining the influence of both.</span>
It used oligarchy, rule by a few.
Because they wanted their own freedom/independence
Because the common people paid all the taxes
Zhu Wen is the one that was not a emperor of the tang dynasty
