the answr is C. the flight of former slaves from the south
The purpose was to transport mail
Answer:
Explanation:In a study published to Proceedings of the National Academy of Sciences, they explain that this new framework could help to prevent future catastrophes as the modern world copes with major societal shifts.
The researchers from the University of Maryland and University College London investigated whether early warning signals are present when an ecosystem begins to show declining resilience.
This phenomenon can indicate the forthcoming of ‘major reorganization,’ or a regime shift within the ecosystem, and subsequently, a collapse.
To do this, they examined 2,378 archaeological sites from nine regions of Neolithic Europe.
In around the 1880s, the Jim Crow laws were passed. The Jim Crow laws are to create segregation between black and white people, because they didn't believe African people had the right to go to a good school around other races.
