What challenges do metropolitan areas face today and how are these challenges being addressed?

What city of ancient russia was heavily influenced by the byzantine merchants?

In what way did expansion and global trade during the 15th to 18th centuries affect the economies of european countries?

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.