Answer: Im sorry but if you have a text book you have to read it off of there then list the page number :/
Explanation:
The United States and the Japanese.
Beautiful cities
recording history
artwork
Decline of Sumer:
Poor irrigation reduced agricultural yields.
Population moved.
Elamite invasion.
<span>One reason that shifting cultivation was so sustainable in the past was because there were just not as many people, the population was much lower overall than it is today, and this provided plenty of open land that could be used solely for cultivation,.</span>
