Problem: As with the minerals discussed above, some vitamins are recognized as organic essential nutrients, necessary in the diet for good health. (Vitamin D is the exception: it can be synthesized in the skin, in the presence of UVB radiation.) Certain vitamin-like compounds that are recommended in the diet, such as carnitine, are thought useful for survival and health, but these are not "essential" dietary nutrients because the human body has some capacity to produce them from other compounds. Moreover, thousands of different phytochemicals have recently been discovered in food (particularly in fresh vegetables), which may have desirable properties including antioxidant activity (see below); however, experimental demonstration has been suggestive but inconclusive. Other essential nutrients that are not classified as vitamins include essential amino acids (see above), choline, essential fatty acids (see above), and the minerals discussed in the preceding section.
What is choline not an example of?
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Answer: vitamins

Problem: By 1975 the majority of local authorities in England and Wales had abandoned the 11-plus examination and moved to a comprehensive system. Over that 10-year period many secondary modern schools and grammar schools were amalgamated to form large neighbourhood comprehensives, whilst a number of new schools were built to accommodate a growing school population. By the mid-1970s the system had been almost fully implemented, with virtually no secondary modern schools remaining. Many grammar schools were either closed or changed to comprehensive status. Some local authorities, including Sandwell and Dudley in the West Midlands, changed all of its state secondary schools to comprehensive schools during the 1970s.
By what year did the 21-plus exam mainly fall out of use?
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Answer: unanswerable

Problem: Seattle's economy is driven by a mix of older industrial companies, and "new economy" Internet and technology companies, service, design and clean technology companies. The city's gross metropolitan product was $231 billion in 2010, making it the 11th largest metropolitan economy in the United States. The Port of Seattle, which also operates SeattleTacoma International Airport, is a major gateway for trade with Asia and cruises to Alaska, and is the 8th largest port in the United States in terms of container capacity. Though it was affected by the Great Recession, Seattle has retained a comparatively strong economy, and remains a hotbed for start-up businesses, especially in green building and clean technologies: it was ranked as America's No. 1 "smarter city" based on its government policies and green economy. In February 2010, the city government committed Seattle to becoming North America's first "climate neutral" city, with a goal of reaching zero net per capita greenhouse gas emissions by 2030.
When does Seattle want to be rated as a climate neutral city?
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Answer:
2030