The Mesopotamians had many achievements related to irrigation, this is because the flooding of the Tigris and Euphrates Rivers can be described as...
Gentle and Unpredictable
Violent and Predictable
Violent and Unpredictable
Gentle and Predictable

If the imperial dynasty had continued to rule china, it is most likely that a) the economy would have improved rather than weakened b) european nations would have gotten more of a foothold in china c) revolutionary groups would not have gained any power in the country d) communism would not have received support among the poor