Problem: Wood:

Abnormal discoloration of wood often denotes a diseased condition, indicating unsoundness. The black check in western hemlock is the result of insect attacks. The reddish-brown streaks so common in hickory and certain other woods are mostly the result of injury by birds. The discoloration is merely an indication of an injury, and in all probability does not of itself affect the properties of the wood. Certain rot-producing fungi impart to wood characteristic colors which thus become symptomatic of weakness; however an attractive effect known as spalting produced by this process is often considered a desirable characteristic. Ordinary sap-staining is due to fungal growth, but does not necessarily produce a weakening effect.

What's the name for the pretty coloring effect caused in some wood by rot-producing fungi?
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A: spalting


Problem: Greeks:

Greek culture has evolved over thousands of years, with its beginning in the Mycenaean civilization, continuing through the Classical period, the Roman and Eastern Roman periods and was profoundly affected by Christianity, which it in turn influenced and shaped. Ottoman Greeks had to endure through several centuries of adversity that culminated in genocide in the 20th century but nevertheless included cultural exchanges and enriched both cultures. The Diafotismos is credited with revitalizing Greek culture and giving birth to the synthesis of ancient and medieval elements that characterize it today.

In what centennial was the massacre of the Greeks of Ottoman descent ?
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A: genocide in the 20th century


Problem: Railway electrification system:

Besides increased efficiency of power plants, there was an increase in efficiency (between 1950 and 1973) of the railway utilization of this electricity with energy-intensity dropping from 218 to 124 kwh/10,000 gross tonne-km (of both passenger and freight trains) or a 43% drop. Since energy-intensity is the inverse of energy-efficiency it drops as efficiency goes up. But most of this 43% decrease in energy-intensity also benefited diesel traction. The conversion of wheel bearings from plain to roller, increase of train weight, converting single track lines to double track (or partially double track), and the elimination of obsolete 2-axle freight cars increased the energy-efficiency of all types of traction: electric, diesel, and steam. However, there remained a 12–15% reduction of energy-intensity that only benefited electric traction (and not diesel). This was due to improvements in locomotives, more widespread use of regenerative braking (which in 1989 recycled 2.65% of the electric energy used for traction,) remote control of substations, better handling of the locomotive by the locomotive crew, and improvements in automation. Thus the overall efficiency of electric traction as compared to diesel more than doubled between 1950 and the mid-1970s in the Soviet Union. But after 1974 (thru 1980) there was no improvement in energy-intensity (wh/tonne-km) in part due to increasing speeds of passenger and freight trains.

Elimination of what helped the efficiency of diesel traction to go up?
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A: 2-axle freight cars


Problem: Gothic architecture:

At the end of the 12th century, Europe was divided into a multitude of city states and kingdoms. The area encompassing modern Germany, southern Denmark, the Netherlands, Belgium, Luxembourg, Switzerland, Austria, Slovakia, Czech Republic and much of northern Italy (excluding Venice and Papal State) was nominally part of the Holy Roman Empire, but local rulers exercised considerable autonomy. France, Denmark, Poland, Hungary, Portugal, Scotland, Castile, Aragon, Navarre, Sicily and Cyprus were independent kingdoms, as was the Angevin Empire, whose Plantagenet kings ruled England and large domains in what was to become modern France. Norway came under the influence of England, while the other Scandinavian countries and Poland were influenced by trading contacts with the Hanseatic League. Angevin kings brought the Gothic tradition from France to Southern Italy, while Lusignan kings introduced French Gothic architecture to Cyprus.

What modern country contains regions in which Plantagenet kings controlled small domains?
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A:
unanswerable