Which of these advances did Han scientists make? Select all that apply. A: developed the concept of zero
B: devised the base-20 number system
C: created more accurate calendars
D: invented the compass
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What would lead a historian to consider two events to have a relationship of correlation rather than causation?

The princes of europe believed that they were no longer obligated to remain under the authority of the church. the idea of another christian church, one outside of the pope's authority, had financial appeal as well. many european leaders began to seize church property and place it under the authority of the state. based on the text, why did another christian church appeal to european princes? it would allow them to make religious decisions. it would give them authority over people. it would allow them to expand their lands. it would allow them to influence the pope.

List two inventions that were invented in the united states before the american civil war