What helped to make the First World War such a long and deadly war? large land areas that troops had to travel over

spy satellites and wireless communication

inventions like the airplane and the machine gun

alliances between Spain, the United States, and Canada

How did the discovery of gold impact american indian territory in the 1870s? a. war broke out among american indian groups when warring chiefs signed new treaties with the government. b. war broke out when white settlers pressured the government to take the land from american indians. c. war broke out when white settlers pressured the government to let american indians keep their land. d. war broke out when white settlers tried to buy land from warring american indian groups.