Problem: 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.
Chinese troops attacked the UN forces when they crossed what river? 
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Answer: the Yalu River


Problem: Interspersed repeats mainly come from transposable elements (TEs), but they also include some protein coding gene families and pseudogenes. Transposable elements are able to integrate into the genome at another site within the cell. It is believed that TEs are an important driving force on genome evolution of higher eukaryotes. TEs can be classified into two categories, Class 1 (retrotransposons) and Class 2 (DNA transposons).
How are pseudogenes classified?
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Answer: unanswerable


Problem: The army's major campaign against the Indians was fought in Florida against Seminoles. It took long wars (1818–58) to finally defeat the Seminoles and move them to Oklahoma. The usual strategy in Indian wars was to seize control of the Indians winter food supply, but that was no use in Florida where there was no winter. The second strategy was to form alliances with other Indian tribes, but that too was useless because the Seminoles had destroyed all the other Indians when they entered Florida in the late eighteenth century.
What did the Army traditionally take control of to defeat the Indians?
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Answer:
winter food supply