Anecessary precondition for a neolithic village to become a civilization in prehistory was the what?

a. use of metals for tools and weapons
b. production of an agricultural surplus
c. construction of walls for defense
d. practice of a religion

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