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In heartwood it occurs only in the first and last forms. Wood that is thoroughly air-dried retains 816% of the water in the cell walls, and none, or practically none, in the other forms. Even oven-dried wood retains a small percentage of moisture, but for all except chemical purposes, may be considered absolutely dry.
What kind of dried wood retains a small quantity of water but is considered absolutely dry?
A: oven-dried

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As advances and specialization have made new scientific research inaccessible to most audiences, the "literary" nature of science writing has become less pronounced over the last two centuries. Now, science appears mostly in journals. Scientific works of Aristotle, Copernicus, and Newton still exhibit great value, but since the science in them has largely become outdated, they no longer serve for scientific instruction. Yet, they remain too technical to sit well in most programmes of literary study. Outside of "history of science" programmes, students rarely read such works.
The literary nature of science writing has become more pronounced during what time period?
A: unanswerable

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On October 2, the Popular Front formally launched its political platform at a two-day congress. Valjas attended, gambling that the front could help Estonia become a model of economic and political revival, while moderating separatist and other radical tendencies. On November 16, 1988, the Supreme Soviet of the Estonian SSR adopted a declaration of national sovereignty under which Estonian laws would take precedence over those of the Soviet Union. Estonia's parliament also laid claim to the republic's natural resources including land, inland waters, forests, mineral deposits, and to the means of industrial production, agriculture, construction, state banks, transportation, and municipal services within the territory of Estonia's borders.
Whose laws would take precedence according to the declaration of national sovereignty?
A: Estonian

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In 1870, Charles Taze Russell and others formed a group in Pittsburgh, Pennsylvania, to study the Bible. During the course of his ministry, Russell disputed many beliefs of mainstream Christianity including immortality of the soul, hellfire, predestination, the fleshly return of Jesus Christ, the Trinity, and the burning up of the world. In 1876, Russell met Nelson H. Barbour; later that year they jointly produced the book Three Worlds, which combined restitutionist views with end time prophecy. The book taught that God's dealings with humanity were divided dispensationally, each ending with a "harvest," that Christ had returned as an invisible spirit being in 1874 inaugurating the "harvest of the Gospel age," and that 1914 would mark the end of a 2520-year period called "the Gentile Times," at which time world society would be replaced by the full establishment of God's kingdom on earth. Beginning in 1878 Russell and Barbour jointly edited a religious journal, Herald of the Morning. In June 1879 the two split over doctrinal differences, and in July, Russell began publishing the magazine Zion's Watch Tower and Herald of Christ's Presence, stating that its purpose was to demonstrate that the world was in "the last days," and that a new age of earthly and human restitution under the reign of Christ was imminent.
In what year did Nelson H. Barbour die?
A:
unanswerable