Problem: Red:

The 19th century also saw the use of red in art to create specific emotions, not just to imitate nature. It saw the systematic study of color theory, and particularly the study of how complementary colors such as red and green reinforced each other when they were placed next to each other. These studies were avidly followed by artists such as Vincent van Gogh. Describing his painting, The Night Cafe, to his brother Theo in 1888, Van Gogh wrote: "I sought to express with red and green the terrible human passions. The hall is blood red and pale yellow, with a green billiard table in the center, and four lamps of lemon yellow, with rays of orange and green. Everywhere it is a battle and antithesis of the most different reds and greens."

Who painted the Night Cafe?
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A: Vincent van Gogh

Problem: The possibility of withdrawal depends on the terms of the treaty and its travaux preparatoire. It has, for example, been held that it is not possible to withdraw from the International Covenant on Civil and Political Rights. When North Korea declared its intention to do this the Secretary-General of the United Nations, acting as registrar, said that original signatories of the ICCPR had not overlooked the possibility of explicitly providing for withdrawal, but rather had deliberately intended not to provide for it. Consequently, withdrawal was not possible.
Who, acting as registrar, informed North Korea that withdrawal was deliberately precluded by the original signatories of the International Covenant on Civil and Political Rights?
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Answer: the Secretary-General of the United Nations

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Mexico City, being the seat of the powers of the Union, did not belong to any particular state but to all. Therefore, it was the president, representing the federation, who used to designate the head of government of the Federal District, a position which is sometimes presented outside Mexico as the "Mayor" of Mexico City.[citation needed] In the 1980s, given the dramatic increase in population of the previous decades, the inherent political inconsistencies of the system, as well as the dissatisfaction with the inadequate response of the federal government after the 1985 earthquake, residents began to request political and administrative autonomy to manage their local affairs.[citation needed] Some political groups even proposed that the Federal District be converted into the 32nd state of the federation.
Who declared the "Mayor" of Mexico City?
A: the president

Context and question: The Indonesian Archipelago is split by the Wallace Line. This line runs along what is now known to be a tectonic plate boundary, and separates Asian (Western) species from Australasian (Eastern) species. The islands between Java/Borneo and Papua form a mixed zone, where both types occur, known as Wallacea. As the pace of development accelerates and populations continue to expand in Southeast Asia, concern has increased regarding the impact of human activity on the region's environment. A significant portion of Southeast Asia, however, has not changed greatly and remains an unaltered home to wildlife. The nations of the region, with only few exceptions, have become aware of the need to maintain forest cover not only to prevent soil erosion but to preserve the diversity of flora and fauna. Indonesia, for example, has created an extensive system of national parks and preserves for this purpose. Even so, such species as the Javan rhinoceros face extinction, with only a handful of the animals remaining in western Java.
What seperates Asian andAustralian species?
Answer: unanswerable

Question: Some Samoans are spiritual and religious, and have subtly adapted the dominant religion of Christianity to 'fit in' with fa'a Samoa and vice versa. As such, ancient beliefs continue to co-exist side-by-side with Christianity, particularly in regard to the traditional customs and rituals of fa'a Samoa. The Samoan culture is centred around the principle of vafealoa'i, the relationships between people. These relationships are based on respect, or fa'aaloalo. When Christianity was introduced in Samoa, most Samoan people converted. Currently 98% of the population identify themselves as Christian.
Is there an answer to this question: What is the practice of Christianity based on?

Answer: unanswerable

Problem: Flowering plant:

The apparently sudden appearance of nearly modern flowers in the fossil record initially posed such a problem for the theory of evolution that it was called an "abominable mystery" by Charles Darwin. However, the fossil record has considerably grown since the time of Darwin, and recently discovered angiosperm fossils such as Archaefructus, along with further discoveries of fossil gymnosperms, suggest how angiosperm characteristics may have been acquired in a series of steps. Several groups of extinct gymnosperms, in particular seed ferns, have been proposed as the ancestors of flowering plants, but there is no continuous fossil evidence showing exactly how flowers evolved. Some older fossils, such as the upper Triassic Sanmiguelia, have been suggested. Based on current evidence, some propose that the ancestors of the angiosperms diverged from an unknown group of gymnosperms in the Triassic period (245202 million years ago). Fossil angiosperm-like pollen from the Middle Triassic (247.2242.0 Ma) suggests an older date for their origin. A close relationship between angiosperms and gnetophytes, proposed on the basis of morphological evidence, has more recently been disputed on the basis of molecular evidence that suggest gnetophytes are instead more closely related to other gymnosperms.[citation needed]

What is missing to show how ancestors of angiosperms diverged from an unknown group?
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A:
unanswerable