Answer: 1 and 3,4. When the first farmers arrived in the Great Plains area, they saw that the plains were hosted by Indians and pastoralists. Over the years, the hostility between these groups has occasionally triggered outbreaks of violence, but in the 1870 's the final victory won the farmers. This was facilitated by the appearance of two inventions. The first of them was barbed wire: thanks to it farmers were able to put fences in places where there was no forest or stones, and cattle could not penetrate the cultivated fields. Another invention was the water pump, which worked from the wind Engine: it saved the lives of farmers during the drought, giving them the opportunity to pump groundwater for irrigation of gardens and for the watering of livestock.
Answer:
1) the use of wind-powered pumps to bring water from deep wells to the surface
3) the invention of barbed wire, which made it possible to fence land
4)new types of farm machinery that made farming on the Plains more efficient
