Estimate of combined pre-columbian population of mexico , central america, south america

by the end of the 20th century most scholars gravitated to a middle estimate of around 50 million, with some historians arguing for an estimate of 100 million or more

The transcontinental railroad provided a means of fast transportation. it cut a 6 month trip into 6 days, created jobs for many people and encouraged immigration. the homestead act played a huge role in western expansion; it allowed settlers to begin a fresh start, and gave them land in exchange for their residence for up to five years and a small fee.