Answer:
a. Voluntary migration is when people migrate to somewhere else on their own accord, of their own free will. Most of the time, voluntary migration happens when someone wants to pursue better economic opportunities or better housing.
b. Voluntary migration is when someone chooses to move. It also includes pull factors like better jobs and better educational resources. Forced migration or involuntary migration is when people have no choice but to move out of their home(s). It includes push factors like war, political instability, and extreme natural disasters like hurricanes or tsunamis (for which they would be forced to migrate as refugees).
c. An economic motivation for migration is better job opportunities, like if the job offered a higher pay, more job stability, or just better job benefits like health insurance.
d. The factors that contributed to the rapid decline in immigration between 1900-1940 is probably due to immigration regulations/quotas being set in the rise of World War I, especially for Europeans. Another factor could be the economic instability that the US was facing, especially during the Great Depression which leads back to Immigration quotas being put in place, which would've made it hard for immigrants to get jobs and things like that and would just be detrimental overall to the US.
e. The immigrant population peak in 1900 had a majority of the immigrants coming from Europe, which is shown by the corresponding color on the graph. However, in 2000, the immigration peak had a much larger diversity with an Asian immigrant majority, as once again shown, with the varying colors on the graph at this time.
f. Some economic factors that motivated immigrants in the late 20th century is better job opportunities, like jobs that paid higher, and better housing, and just an overallhigher standard of living. The US was known for these things, and so many people would immigrate here looking for things like "the American Dream," which for most, included bettering their economic situation.
g. Chain migration is when migrants from an area follow previous migrants to the same destination. An example would be Chinatown in San Francisco. Chain migrations impact the cultural landscape by creating enclaves of similar immigrants. In large cities like New York, it essentially creates smaller, ethnically similar, mini cities.