The Mayans first came up with the idea to use canals and trenches dug up with islands of land in between them. This would come from a water source such as a major river. The crops would then be constantly surrounded by water.
The Louisiana Purchase significantly increased the size of the United States, which began the expansion of the country towards the West.<span> It also laid the groundwork for the Civil War as the new territories took sides in the heated slavery debate.
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The opium war led to expanision of western influence in china and caused great social and economical disruption, with the wars weakening the dynastic system and paving the way for uprisings such as the boxer rebellions. and as dar es exonomical disruption, upon loosing the war china was forced to pay out 21million dollars per the treaty of nanjing. hope this helps:)
