Which groups of people made up most of the workers on the railroad?

a. chinese and irish immigrants, and african americans

b. factory workers, cattle ranchers, and sailors

c. native americans, mexican americans, and south americans

d. confederates, abolitionists, and free masons

The correct answer is A. Chinese and Irish immigrants, and African Americans

Explanation:

In the United States, the development of railroad transportation along with the construction of railroads all over the country took place mainly during the 18th and 19th centuries. This included the construction of massive railroad systems such as First Transcontinental Road. In terms of workers, most workers in these constructions were African Americans (former slaves looking for opportunities) or immigrants from countries such as China or Ireland who immigrated looking for better living conditions. For example, the Central Pacific Road was mainly constructed by Chinese immigrants. According to this the groups of people that made up most of the workers on the railroad were Chinese and Irish immigrants and African Americans.

early human migrations are the earliest migrations and expansions of archaic and modern humans across continents and are believed to have begun approximately 2 million years ago with the out of africa migration of homo erectus. this initial migration was followed by other archaic humans including h. heidelbergensis, which lived around 500,000 years ago and was the likely ancestor of both denisovans and neanderthals. early hominids were said to have "crossed land bridges that were eventually covered in water" .

within africa, homo sapiens dispersed around the time of its speciation, roughly 300,000 years ago.the "recent african origin" paradigm suggests that the anatomically modern humans outside of africa descend from a population of homo sapiens migrating from east africa roughly 70,000 years ago and spreading along the southern coast of asia and to oceania before 50,000 years ago. modern humans spread across europe about 40,000 years ago.

the migrating modern human populations are known to have interbred with local varieties of archaic humans, so that contemporary human populations are descended in small part (below 10% contribution) from regional varieties of archaic humans.

after the last glacial maximum, north eurasian populations migrated to the americas about 20,000 years ago. northern eurasia was peopled after 12,000 years ago, in the beginning holocene. arctic canada and greenland were reached by the paleo-eskimo expansion around 4,000 years ago. finally, polynesia was peopled after 2,000 years ago, by the austronesian expansion.

theodore roosevelt challenged william to a duel, whoever won, got their policy sent to congress. it ended up in a stalemate, and both men were injured and sent to the hospital.