By 1900 the American nation had established itself as a world power. The West was won. The frontier -- the great fact of 300 years of American history -- was no more. The continent was settled from coast to coast. Apache war chief Geronimo had surrendered in 1886. Defeat of the Sioux at the battle of Wounded Knee in 1891 had brought the Indian Wars to a close. By 1900 the Indians were on reservations and the buffalo were gone. Homesteading and the introduction of barbed wire in 1874 had brought an end to the open range. The McCormick reaper had made large-scale farming profitable and, in 1900, the U.S. was by far the world's largest agricultural producer. The first transcontinental rail link had been completed in 1869. Three decades later, in 1900, the nation had 193,000 miles of track, with five railroad systems spanning the continent
Probably because in the south, the farmers needed help with gathering alot of crops, such as cotton. In the north, they didn't have farms, so they didn't need slaves.
The term that takes into consideration "how humans adapt to and modify the environment is human-environment interaction. Correct answer:C
The term denotes the interactions between the human social system and his environment (the erst of the ecosystem). These interactions include how humans depend on the environment, how humans modify the environment and the way humans adapt to the environment.
