What did Jacob Riis do

Jacob Riis, in full Jacob August Riis, (born May 3, 1849,  Denmark—died May 26, 1914, Barre, Massachusetts, U.S.), American newspaper reporter, social reformer, and photographer who, with his book How the Other Half Lives (1890), shocked the conscience of his readers with factual descriptions of slum conditions in New York City.

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2686-2181 bce-- "egyptian civilization developed along the nile river in large part because the river’s annual flooding ensured reliable, rich soil for growing crops."

1069-664 bce-- "ancient egyptians developed wide-reaching trade networks along the nile, in the red sea, and in the near east."

c) troops march forward in close formation against newer, more accurate weapons