[Q]: Extract the answer to the question from the following context. Question: When did federalism stopped to mean treaty? Context: The terms 'federalism' and 'confederalism' both have a root in the Latin word foedus, meaning treaty, pact or covenant. Their common meaning until the late eighteenth century was a simple league or inter-governmental relationship among sovereign states based upon a treaty. They were therefore initially synonyms. It was in this sense that James Madison in Federalist 39 had referred to the new United States as 'neither a national nor a federal Constitution, but a composition of both' (ie. neither a single large unitary state nor a league/confederation among several small states, but a hybrid of the two). In the course of the nineteenth century the meaning of federalism would come to shift, strengthening to refer uniquely to the novel compound political form, while the meaning of confederalism would remain at a league of states. Thus, this article relates to the modern usage of the word 'federalism'.
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[A]: nineteenth century
input: Please answer the following: Extract the answer to the question from the following context. Question: When do the leaves turn colors? Context: In nature, the red color of blood comes from hemoglobin, the iron-containing protein found in the red blood cells of all vertebrates. The red color of the Grand Canyon and other geological features is caused by hematite or red ochre, both forms of iron oxide. It also causes the red color of the planet Mars. The red sky at sunset and sunrise is caused by an optical effect known as Rayleigh scattering, which, when the sun is low or below the horizon, increases the red-wavelength light that reaches the eye. The color of autumn leaves is caused by pigments called anthocyanins, which are produced towards the end of summer, when the green chlorophyll is no longer produced. One to two percent of the human population has red hair; the color is produced by high levels of the reddish pigment pheomelanin (which also accounts for the red color of the lips) and relatively low levels of the dark pigment eumelanin.
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output: when the green chlorophyll is no longer produced
Please answer this: Extract the answer to the question from the following context. Question: Why was the original writing postponed? Context: From 1962 until his retirement in 1968, he was a professor at the University of Freiburg, West Germany, where he began work on his next book, Law, Legislation and Liberty. Hayek regarded his years at Freiburg as "very fruitful". Following his retirement, Hayek spent a year as a visiting professor of philosophy at the University of California, Los Angeles, where he continued work on Law, Legislation and Liberty, teaching a graduate seminar by the same name and another on the philosophy of social science. Primary drafts of the book were completed by 1970, but Hayek chose to rework his drafts and finally brought the book to publication in three volumes in 1973, 1976 and 1979.
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Answer: Hayek chose to rework his drafts
Problem: Extract the answer to the question from the following context. Question: What does class help define? Context: The second approach to the problem took as its base the notion of class, and defines a set as a class which belongs to other classes, while a proper class is defined as a class which does not belong to other classes. Under the ZermeloFraenkel approach, the axioms impede the construction of a set of all sets which do not belong to themselves. In contrast, under the von Neumann approach, the class of all sets which do not belong to themselves can be constructed, but it is a proper class and not a set.

A: a set
Problem: Given the question: Extract the answer to the question from the following context. Question: What makes more than a duo of hydrogen bonds? Context: Two chains of DNA twist around each other to form a DNA double helix with the phosphate-sugar backbone spiralling around the outside, and the bases pointing inwards with adenine base pairing to thymine and guanine to cytosine. The specificity of base pairing occurs because adenine and thymine align form two hydrogen bonds, whereas cytosine and guanine form three hydrogen bonds. The two strands in a double helix must therefore be complementary, with their sequence of bases matching such that the adenines of one strand are paired with the thymines of the other strand, and so on.:4.1
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The answer is:
cytosine and guanine form three hydrogen bonds
Problem: Extract the answer to the question from the following context. Question: Where was Abdel Nasser Hussein from? Context: Gamal Abdel Nasser was born on 15 January 1918 in Bakos, Alexandria, the first son of Fahima and Abdel Nasser Hussein. Nasser's father was a postal worker born in Beni Mur in Upper Egypt and raised in Alexandria, and his mother's family came from Mallawi, el-Minya. His parents married in 1917, and later had two more boys, Izz al-Arab and al-Leithi. Nasser's biographers Robert Stephens and Said Aburish wrote that Nasser's family believed strongly in the "Arab notion of glory", since the name of Nasser's brother, Izz al-Arab, translates to "Glory of the Arabs"a rare name in Egypt.

A:
Beni Mur in Upper Egypt