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By 1836, the Duchess's brother, Leopold, who had been King of the Belgians since 1831, hoped to marry his niece to his nephew, Prince Albert of Saxe-Coburg and Gotha. Leopold, Victoria's mother, and Albert's father (Ernest I, Duke of Saxe-Coburg and Gotha) were siblings. Leopold arranged for Victoria's mother to invite her Coburg relatives to visit her in May 1836, with the purpose of introducing Victoria to Albert. William IV, however, disapproved of any match with the Coburgs, and instead favoured the suit of Prince Alexander of the Netherlands, second son of the Prince of Orange. Victoria was aware of the various matrimonial plans and critically appraised a parade of eligible princes. According to her diary, she enjoyed Albert's company from the beginning. After the visit she wrote, "[Albert] is extremely handsome; his hair is about the same colour as mine; his eyes are large and blue, and he has a beautiful nose and a very sweet mouth with fine teeth; but the charm of his countenance is his expression, which is most delightful." Alexander, on the other hand, was "very plain".
What year did Leopold become King of the Belgiums?
A: unanswerable

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In his usurpation of the throne from the Jianwen Emperor (r. 1398–1402), the Yongle Emperor was aided by the Buddhist monk Yao Guangxiao, and like his father, the Hongwu Emperor, the Yongle Emperor was "well-disposed towards Buddhism", claims Rossabi. On March 10, 1403, the Yongle Emperor invited Deshin Shekpa, 5th Karmapa Lama (1384–1415), to his court, even though the fourth Karmapa had rejected the invitation of the Hongwu Emperor. A Tibetan translation in the 16th century preserves the letter of the Yongle Emperor, which the Association for Asian Studies notes is polite and complimentary towards the Karmapa. The letter of invitation reads,
Who aided the Yongle Emperor?
A: the Buddhist monk Yao Guangxiao

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The nickel hydrogen battery was used for the first time in 1977 aboard the U.S. Navy's Navigation technology satellite-2 (NTS-2). For example, the ISS, Mars Odyssey and the Mars Global Surveyor are equipped with nickel-hydrogen batteries. In the dark part of its orbit, the Hubble Space Telescope is also powered by nickel-hydrogen batteries, which were finally replaced in May 2009, more than 19 years after launch, and 13 years over their design life.
What year was the first nickel hydrogen battery used?
A: 1977

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According to the Sixth China Census, the total population of the City of Nanjing reached 8.005 million in 2010. The statistics in 2011 estimated the total population to be 8.11 million. The birth rate was 8.86 percent and the death rate was 6.88 percent. The urban area had a population of 6.47 million people. The sex ratio of the city population was 107.31 males to 100 females.
What was Nanjing's birth rate?
A:
8.86 percent