Why are the Ghana, Mali, and Songhai kingdoms important for our larger study of the Middle Ages across the globe?

i think it was   tsar alexander ii

the noble might have thought that the system was far because they had lot of things and riches and the serf would have thought that the feudal system was un fair because of the way they were treated.

the graph shows the spread of railways in the 1800s.

based on the graph, the conclusion that can be drawn about germany is answer d)   by 1880, germany had more rail lines than great britain and russia.

which statement explains one of the reasons world war 1 was so much more destructive than earlier conflicts