Approximately how many children worked in factories in 1900?

(d) rivers.

explanation:

civilizations developed around rivers because their waters provided places to hunt and fish. also, as the rivers flooded, the lands around them became fertile. this allowed them to support farming. this is especially true of the nile river, which flooded the same time each year.

theodore roosevelt challenged william to a duel, whoever won, got their policy sent to congress. it ended up in a stalemate, and both men were injured and sent to the hospital.