The industrial revolution indeed was a great factor in the growth of population in industrialized countries. The population in industrialized countries had a sudden rise or increase due to the bigger and greater opportunities provided by the country thus, alluring more people to migrate.
Answer:
Pioneer settlers were sometimes pulled west because they wanted to make a better living. Others received letters from friends or family members who had moved west. These letters often told about a good life on the frontier. The biggest factor that pulled pioneers west was the opportunity to buy land
Tension.
Because the Cold War marked a time period of geopolitical tension between the Soviet Union with its satellite states and the United States with its allies following World War II.
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