Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
From the 9th century, the Pecheneg nomads began an uneasy relationship with Kievan Rus. For over two centuries they launched sporadic raids into the lands of Rus, which sometimes escalated into full-scale wars (such as the 920 war on the Pechenegs by Igor of Kiev reported in the Primary Chronicle), but there were also temporary military alliances (e.g. the 943 Byzantine campaign by Igor). In 968, the Pechenegs attacked and besieged the city of Kiev. Some speculation exists that the Pechenegs drove off the Tivertsi and the Ulichs to the regions of the upper Dniester river in Bukovina. The Byzantine Empire was known to support the Pechenegs in their military campaigns against the Eastern Slavic states.[citation needed]
What did the Pecheneg frequently not do over the span of two centuries?
A: unanswerable

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Moisture absorption occurs when the material is exposed to high humidity or water. Both the resin and the reinforcement may absorb water; water may be also soaked by capillary forces through voids in the materials and along the reinforcement. Epoxies of the FR-4 materials aren't too susceptible, with absorption of only 0.15%. Teflon has very low absorption of 0.01%. Polyimides and cyanate esters, on the other side, suffer from high water absorption. Absorbed water can lead to significant degradation of key parameters; it impairs tracking resistance, breakdown voltage, and dielectric parameters. Relative dielectric constant of water is about 73, compared to about 4 for common circuitboard materials. Absorbed moisture can also vaporize on heating and cause cracking and delamination, the same effect responsible for "popcorning" damage on wet packaging of electronic parts. Careful baking of the substrates may be required.
What percentage absorption do F-4 epoxies have?
A: 0.15%

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A "grand", sometimes shortened to simply "G", is a common term for the amount of $1,000. The suffix "K" or "k" (from "kilo-") is also commonly used to denote this amount (such as "$10k" to mean $10,000). However, the $1,000 note is no longer in general use. A "large" or "stack", it is usually a reference to a multiple of $1,000 (such as "fifty large" meaning $50,000). The $100 note is nicknamed "Benjamin", "Benji", "Ben", or "Franklin" (after Benjamin Franklin), "C-note" (C being the Roman numeral for 100), "Century note" or "bill" (e.g. "two bills" being $200). The $50 note is occasionally called a "yardstick" or a "grant" (after President Ulysses S. Grant, pictured on the obverse). The $20 note is referred to as a "double sawbuck", "Jackson" (after Andrew Jackson), or "double eagle". The $10 note is referred to as a "sawbuck", "ten-spot" or "Hamilton" (after Alexander Hamilton). The $5 note as "Lincoln", "fin", "fiver" or "five-spot". The infrequently-used $2 note is sometimes called "deuce", "Tom", or "Jefferson" (after Thomas Jefferson). The $1 note as a "single" or "buck". The dollar has also been, referred to as a "bone" and "bones" in plural (e.g. "twenty bones" is equal to $20). The newer designs, with portraits displayed in the main body of the obverse rather than in cameo insets upon paper color-coded by denomination, are sometimes referred to as "bigface" notes or "Monopoly money".
Which note is occasionally called a largestick?
A: unanswerable

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To make pulp from wood, a chemical pulping process separates lignin from cellulose fibres. This is accomplished by dissolving lignin in a cooking liquor, so that it may be washed from the cellulose; this preserves the length of the cellulose fibres. Paper made from chemical pulps are also known as wood-free papersnot to be confused with tree-free paper; this is because they do not contain lignin, which deteriorates over time. The pulp can also be bleached to produce white paper, but this consumes 5% of the fibres; chemical pulping processes are not used to make paper made from cotton, which is already 90% cellulose.
What percentage of fibres are used in the bleaching process?
A:
unanswerable