What were two causes of the movement known as the great migration during the early twentieth century? a. the irish potato famine and the seizure of farmland by the british government for taxes b. jim crow laws and lack of job opportunities for african americans in the southern states c. the need for railroad workers and the increase in ship transportation between china and the western united states d. programs against jews in russia and the lack of freedom of religion in eastern europe

by 1890, the united states had by far the world's most productive economy. american industry produced twice as much as its closest competitor--britain. but the united states was not a great military or diplomatic power. its army numbered less than 30,000 troops, and its navy had only about 10,000 seamen. britain's army was five times the size of its american counterpart, and its navy was ten times bigger. the united states' military was small because the country was situated between two large oceans and was surrounded by weak or friendly nations. it faced no serious military threats and had little interest in asserting military power overseas.