Problem: National Archives and Records Administration:

Libraries and museums have been established for other presidents, but they are not part of the NARA presidential library system, and are operated by private foundations, historical societies, or state governments, including the Abraham Lincoln, Rutherford B. Hayes, William McKinley, Woodrow Wilson and Calvin Coolidge libraries. For example, the Abraham Lincoln Presidential Library and Museum is owned and operated by the state of Illinois.

What groups help fund NARA to support libraries and museums?
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A: unanswerable


Problem: Education:

At the level of the individual, there is a large literature, generally related to the work of Jacob Mincer, on how earnings are related to the schooling and other human capital. This work has motivated a large number of studies, but is also controversial. The chief controversies revolve around how to interpret the impact of schooling. Some students who have indicated a high potential for learning, by testing with a high intelligence quotient, may not achieve their full academic potential, due to financial difficulties.[citation needed]

Why do some kids achieve their full academic potential easily?
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A: unanswerable


Problem: Green:

The modern English word green comes from the Middle English and Anglo-Saxon word grene, from the same Germanic root as the words "grass" and "grow". It is the color of living grass and leaves and as a result is the color most associated with springtime, growth and nature. By far the largest contributor to green in nature is chlorophyll, the chemical by which plants photosynthesize and convert sunlight into chemical energy. Many creatures have adapted to their green environments by taking on a green hue themselves as camouflage. Several minerals have a green color, including the emerald, which is colored green by its chromium content.

What chemical causes emeralds to be green?
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A: chromium


Problem: Namibia:

The Kalahari Desert, an arid region shared with South Africa and Botswana, is one of Namibia's well-known geographical features. The Kalahari, while popularly known as a desert, has a variety of localised environments, including some verdant and technically non-desert areas. One of these, known as the Succulent Karoo, is home to over 5,000 species of plants, nearly half of them endemic; Approximately 10 percent of the world's succulents are found in the Karoo. The reason behind this high productivity and endemism may be the relatively stable nature of precipitation.

What Desert is shared between South Africa and Botswana?
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A:
Kalahari Desert