The correct answer to this open question is the following.
The changes to Chinese administration and bureaucracy that Song rulers introduced were the following.
The Song dynasty produced changes in ancient China. Its leaders were committed to work and develop notorious advancements such as the use of the compass for exploration, the use of gunpowder to wage war and other uses such as construction, and invested so much in the formation of its standing navy, culture, arts, education, literature, and philosophical studies. Confucianism had a second "fresh air" with the studies of philosophers such as Zhu Xi and Cheng Yi.
Bureaucracy was centralized under the Song dynasty and demanded its bureaucratic officials to work with virtue and high moral. Indeed, they had to pass difficult examinations and evaluations to be part of the Song bureaucratic system of government.
The Song dynasty started in 960 and ended in 1279.
Technology helps in dealing with economic emergencies like food shortage and disasters. Technology is used to study the existing environmental conditions in order for farmers to be guided with the right crops to plant at specific seasons to ensure maximum yields. In terms of disasters, technology is used for disaster risk reduction and management. This is done in order to minimize the effects that disasters have on the resources.
The Aztec empire was ruled by one ruler where the Mayan had rule divided among the different states
In the early 1900's, 6 million African Americans emigrated form the rural south of the US to the northeast, mid-west and west and thus began an urban existence in many of the cities in these areas so became important politically due to their numbers and their strong support of the civil rights movement later on.
Christianity, decadence, the metal lead in the water supply, monetary trouble, and military problems caused the fall of rome.
