Which is necessary for a society to be considered a civilization? choose all answers that are correct. a. literature b. division of labor c. a hierarchy of priests d. more food than is needed for survival e. organized schools

worldwide, 780 million people do not have access to an improved water source. an estimated 2.5 billion people lack access to improved sanitation (more than 35% of the world's population)

b. ensure mutual protection from communism.

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