Answer: California and New Mexico became new states.
Explanation: K12 Quiz
In the context of World War II, the 'Big Three' consisted of the leaders of the three most powerful countries on the side of the Allies. They were Winston Churchill, the Prime Minister of Great Britain, Franklin D. Roosevelt, the President of the United States, and Joseph Stalin, the Premier of the Soviet Union.
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Britian because america at the time was still not powerful enough to fight it alone without the help of the french soldiers