The problem: Answer a question about this article:
Besides the bit rate of an encoded piece of audio, the quality of MP3 files also depends on the quality of the encoder itself, and the difficulty of the signal being encoded. As the MP3 standard allows quite a bit of freedom with encoding algorithms, different encoders may feature quite different quality, even with identical bit rates. As an example, in a public listening test featuring two different MP3 encoders at about 128 kbit/s, one scored 3.66 on a 15 scale, while the other scored only 2.22.
To compare qualities, sound files are evaluated on a scale that ranges from 1 to what?
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The answer: 5

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In soil, microorganisms that reside in the rhizosphere (a zone that includes the root surface and the soil that adheres to the root after gentle shaking) carry out nitrogen fixation, converting nitrogen gas to nitrogenous compounds. This serves to provide an easily absorbable form of nitrogen for many plants, which cannot fix nitrogen themselves. Many other bacteria are found as symbionts in humans and other organisms. For example, the presence of over 1,000 bacterial species in the normal human gut flora of the intestines can contribute to gut immunity, synthesise vitamins, such as folic acid, vitamin K and biotin, convert sugars to lactic acid (see Lactobacillus), as well as fermenting complex undigestible carbohydrates. The presence of this gut flora also inhibits the growth of potentially pathogenic bacteria (usually through competitive exclusion) and these beneficial bacteria are consequently sold as probiotic dietary supplements.
What is the amount of bacteria in human intestines?
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The answer: over 1,000 bacterial species

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Different societies apply differing criteria regarding who is classified as "black", and these social constructs have also changed over time. In a number of countries, societal variables affect classification as much as skin color, and the social criteria for "blackness" vary. For example, in North America the term black people is not necessarily an indicator of skin color or majority ethnic ancestry, but it is instead a socially based racial classification related to being African American, with a family history associated with institutionalized slavery. In South Africa and Latin America, for instance, mixed-race people are generally not classified as "black." In South Pacific regions such as Australia and Melanesia, European colonists applied the term "black" or it was used by populations with different histories and ethnic origin.
How is the term "black" defined in the United States?
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The answer: it is instead a socially based racial classification related to being African American, with a family history associated with institutionalized slavery.

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Red is the traditional color of warning and danger. In the Middle Ages, a red flag announced that the defenders of a town or castle would fight to defend it, and a red flag hoisted by a warship meant they would show no mercy to their enemy. In Britain, in the early days of motoring, motor cars had to follow a man with a red flag who would warn horse-drawn vehicles, before the Locomotives on Highways Act 1896 abolished this law. In automobile races, the red flag is raised if there is danger to the drivers. In international football, a player who has made a serious violation of the rules is shown a red penalty card and ejected from the game.
What did a red flag signal in the Middle Ages?
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The answer:
defenders of a town or castle would fight to defend it