What are the political, social, and economic consequences of new modes of communication and transportation after 1900?

Why did river valleys most farming impact the lives of neolithic peoples?

How did american entry into world war i affect the allied powers?

Historians have recently discovered a historical journal published in the early twentieth century. the journal contains facts based on original sources about the downfall of the early byzantium empire. historians consider this long-lost journal to be a breakthrough in their understanding of the byzantium empire. based on this information, the journal is a source.