The problem: Answer a question about this article:
In 1995, Oklahoma City was the site of one of the most destructive acts of domestic terrorism in American history. The Oklahoma City bombing of April 19, 1995, in which Timothy McVeigh and Terry Nichols detonated an explosive outside of the Alfred P. Murrah Federal Building, killed 168 people, including 19 children. The two men were convicted of the bombing: McVeigh was sentenced to death and executed by the federal government on June 11, 2001; his partner Nichols is serving a sentence of life in prison without the possibility of parole. McVeigh's army buddy, Michael Fortier, was sentenced to 12 years in federal prison and ordered to pay a $75,000 fine for his role in the bombing plot (i.e. assisting in the sale of guns to raise funds for the bombing, and examining the Murrah Federal building as a possible target before the terrorist attack). His wife, Lori Fortier, who has since died, was granted immunity from prosecution in return for her testimony in the case.
Who committed the Oklahoma City Bombing?
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The answer: Timothy McVeigh and Terry Nichols

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According to the 2000 edition of a popular physical anthropology textbook, forensic anthropologists are overwhelmingly in support of the idea of the basic biological reality of human races. Forensic physical anthropologist and professor George W. Gill has said that the idea that race is only skin deep "is simply not true, as any experienced forensic anthropologist will affirm" and "Many morphological features tend to follow geographic boundaries coinciding often with climatic zones. This is not surprising since the selective forces of climate are probably the primary forces of nature that have shaped human races with regard not only to skin color and hair form but also the underlying bony structures of the nose, cheekbones, etc. (For example, more prominent noses humidify air better.)" While he can see good arguments for both sides, the complete denial of the opposing evidence "seems to stem largely from socio-political motivation and not science at all". He also states that many biological anthropologists see races as real yet "not one introductory textbook of physical anthropology even presents that perspective as a possibility. In a case as flagrant as this, we are not dealing with science but rather with blatant, politically motivated censorship".
What does Gill think the complete denial of opposing evidence stems from?
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The answer: socio-political motivation

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Energy production in Greece is dominated by the Public Power Corporation (known mostly by its acronym , or in English DEI). In 2009 DEI supplied for 85.6% of all energy demand in Greece, while the number fell to 77.3% in 2010. Almost half (48%) of DEI's power output is generated using lignite, a drop from the 51.6% in 2009. Another 12% comes from Hydroelectric power plants and another 20% from natural gas. Between 2009 and 2010, independent companies' energy production increased by 56%, from 2,709 Gigawatt hour in 2009 to 4,232 GWh in 2010.
What percentage did independent companies' energy production increase between 2009 and 2010?
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The answer: 56%

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Although an alloy is technically an impure metal, when referring to alloys, the term "impurities" usually denotes those elements which are not desired. These impurities are often found in the base metals or the solutes, but they may also be introduced during the alloying process. For instance, sulfur is a common impurity in steel. Sulfur combines readily with iron to form iron sulfide, which is very brittle, creating weak spots in the steel. Lithium, sodium and calcium are common impurities in aluminium alloys, which can have adverse effects on the structural integrity of castings. Conversely, otherwise pure-metals that simply contain unwanted impurities are often called "impure metals" and are not usually referred to as alloys. Oxygen, present in the air, readily combines with most metals to form metal oxides; especially at higher temperatures encountered during alloying. Great care is often taken during the alloying process to remove excess impurities, using fluxes, chemical additives, or other methods of extractive metallurgy.
What is a characteristic of iron sulfide?
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The answer:
very brittle