Extract the answer to the question from the following context. Question: Why do people have such broad ethnic origins? Context: One problem with these assignments is admixture. Many people have a highly varied ancestry. For example, in the United States, colonial and early federal history were periods of numerous interracial relationships, both outside and inside slavery. This has resulted in a majority of people who identify as African American having some European ancestors. Similarly, many people who identify as white have some African ancestors. In a survey in a northeastern U.S. university of college students who identified as "white", about 30% were estimated to have up to 10% African ancestry.
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Answer: colonial and early federal history were periods of numerous interracial relationships

Extract the answer to the question from the following context. Question: Which specific unit sold less than 2 millions units? Context: While the original Xbox sold poorly in Japan, selling just 2 million units while it was on the market (between 2002 and 2005),[citation needed] the Xbox 360 sold even more poorly, selling only 1.5 million units from 2005 to 2011. Edge magazine reported in August 2011 that initially lackluster and subsequently falling sales in Japan, where Microsoft had been unable to make serious inroads into the dominance of domestic rivals Sony and Nintendo, had led to retailers scaling down and in some cases discontinuing sales of the Xbox 360 completely.
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Answer: 360

Extract the answer to the question from the following context. Question: What setback did the UN forces experience? Context: The war started badly for the US and UN. North Korean forces struck massively in the summer of 1950 and nearly drove the outnumbered US and ROK defenders into the sea. However the United Nations intervened, naming Douglas MacArthur commander of its forces, and UN-US-ROK forces held a perimeter around Pusan, gaining time for reinforcement. MacArthur, in a bold but risky move, ordered an amphibious invasion well behind the front lines at Inchon, cutting off and routing the North Koreans and quickly crossing the 38th Parallel into North Korea. As UN forces continued to advance toward the Yalu River on the border with Communist China, the Chinese crossed the Yalu River in October and launched a series of surprise attacks that sent the UN forces reeling back across the 38th Parallel. Truman originally wanted a Rollback strategy to unify Korea; after the Chinese successes he settled for a Containment policy to split the country. MacArthur argued for rollback but was fired by President Harry Truman after disputes over the conduct of the war. Peace negotiations dragged on for two years until President Dwight D. Eisenhower threatened China with nuclear weapons; an armistice was quickly reached with the two Koreas remaining divided at the 38th parallel. North and South Korea are still today in a state of war, having never signed a peace treaty, and American forces remain stationed in South Korea as part of American foreign policy.
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Answer:
a series of surprise attacks