The majority of immigrants and rural migrants who moved to american cities at the turn of the twentieth century became part of

a. middle class.
b. working poor.
c. wealthy class.
d. working rich.

I believe the answer is: working poor

Working poor refers to the group of people who are in poverty level due to lack of work hours/opportunity. The majority of immigrants came to American cities to gamble their opportunities and hope that they managed to get job in recently established manufacture companies. Only some of them able to got the jobs.

nuclear fission produces the atomic bomb, a weapon of mass destruction that uses power released by the splitting of atomic nuclei the fighting in iwo jima and okinawa affected the allies' pacific strategy because truman decided to drop the atomic bomb on mainland japan.