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Irrigation was a Sumerian invention, which included major components like canals, gated ditches, levees, and gates. Its two purposes were to (1) to water the crops using w<span>ater carried from the Tigris and Euphrates Rivers to the fields where the crops were located, and (2) </span><span>to protect Mesopotamia, from the threat of flooding.</span>
<span>Most of the South American carriages are concentrated in rivers; ports with indigenous tribal areas and connect in groups of small cities. Thus the main and oldest roads of these regions were built, which go from that point to the other concentrated between rivers and plateaus by means of connections and other alternate routes.</span>
It grants congress the powers implied in the constitution ,but that are not explicitly stated.
