What is the most important reason for the end of the western roman empire

How did german physicist werner heisenberg's uncertainty principle shake beliefs in newtonian physics?

Which statement about submarine use in world war i is true? the allies never found a way to counter german submarine warfare. germany’s use of submarines affected the united states’ decision to enter the war. only the germans used submarines in world war i.

What was a challenge for president truman’s political agenda in 1950