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Study the graph and then complete the analysis of the data by filling in the missing information.

In a modern democracy all elected officials serve for a certain number of terms then must retire a high school sophomore and a senior citizen may vote at the polls together a united states senator votes on immigration law on behalf of your mother through indirect ballot all democracies have a two chamber system of representation united states citizens live in a direct democracy

What is the main difference between primary and secondary sources? a. primary sources are historical documents, and secondary sources are modern-day documents. b. primary sources are derived from museums and archives, and secondary sources are created by history students and academics. c. primary sources are found in ancient places with a rich history, and secondary sources are found in historical journals and blogs. d. primary sources are created during a particular historical era, and secondary sources are created by studying primary sources.