In what year did the United States enter WW II?
1941
1941
1941
1941
1941
1941
1941
1941
1941
1941
1941
1941
1941
1941
1940
1941
1940
1941
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1941.
1939
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1939
1942
1941.
1942
1939
1942
1939
7th of December 1941
1942
1941-Japan
1941.
1939
1942
7th of December 1941
1942
1939
1939.
1942
1941-Japan
1941.
7th of December 1941
1940-July
1940.
1939
December 1941
1941-July
1939.
1942
7 December 1941
1939
1942
1941.
December 1941
1939.
1941-Japan
7th of December 1941
1942
1940.
1939
December 1941
7 December 1941
1941 & 1942
1939.
1942
1941.
1940-July
1941-July
1939
December 1941
1940-41
1942
7 December 1941
1939.
7th of December 1941
1941-Japan
1941 – 1942
1940.
1939
1942
1941.
December 1941
1941 & 1942
1941–1944
1941–1942
1941–1945
7 December 1941
1942
1941–1956
7th of December 1941
1939
December 1941
1940-41
1939.
1941-Japan
1941–1944
1941–1942
1941.
1941–1945
1941-July
1941 & 1942
1941 – 1942
1940-05
7 December 1941.
7 December 1941
1940.
1941–1956
1939
December 1941
1940-39
1941-05
1939.
1942.
1941–1939
1941 – 79
7th of December 1940
1941–1944
1941–1942
Pearl Harbor
7 December 1941
1940-41
1941.
1941–1945
December 1941
1941 – 1942
1941 & 1943
7 December 1941.
1939.
1941 & 1942
1940.
1941–1956
1941 & 1942.
1941 – 79
1940-1939
1941–1945.
1941-July
1943
1940-05
Pearl Harbor
Y2K
1940-39
December 1941
Pearl Harbor, 1941
7th of December 1940
1940-42
1941–1944
1941–1942
1941 & 1943
1942.
1941-05
7 December 1941
1940-41
1939.
1941 & 1944
1941.
1941–1945
1941 – 1941
1940-1940
1941 - 1942
1943
7th of September 1941
7th of January 1941
1941–1939
1941-42
Pearl Harbor
1940.