Answer:
European colonization, migration, missionaries, and trade
Explanation:
C. the republic and empire both had a professional army
they were already unreachable but archers helped too
Explanation:
In order to prevent an enemy getting over the wall the castle builders selected their site with great care so that the terrain would be difficult for a belfry to cross. They then made it more difficult by digging a ditch or moat around the curtain walls in order to prevent the towers getting close to the battlements. yet archers played a great role in middle ages by defended castles and kingdoms from top while infantry troops fought.
Article IV (four) of the Constitution of the US discusses the obligations of the national government to the state and the obligation of the states to each other.
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