Refer to the map below to answer the following question: What factors explain the major increase in population in half of China and a much smaller change in the other half?

an invasion from the north and rich farmland to the south
an invasion from the south and rich farmland to the north
overland trade and urbanization
seagoing trade and urbanization

Which effect did the united states supreme court's decision in plessy v. ferguson have? 1. ending segregation in all public schools in america 2. protecting voting rights for african americans by eliminating literacy tests 3. upholding the rights of all citizens to be treated equally by the government 4. authorizing the system that kept black and white people separated