Which is likely to take the most amount of time for a computer to simulate?

World War II officially began when: 

What directly followed after the Japanese attack on Pearl Harbor, Hawaii:

With the end of World War II, women workers were encouraged to 

Whose music revolutionized the music industry in the late 1950s and early 1960s?

In the early 1940s, what was Japan’s wartime motivation? 

By 1947, the intense rivalry between the Soviet Union and the United States was being called:

In 1945, this individual formed a provisional government in Hanoi and declared independence from France.

Four students were killed by the National Guard at Kent State University during a protest of:

The invasion of what country provoked England and France to declare war on Germany?