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In response to the pressure on Hot AC, a new kind of AC format cropped up among American radio recently. The urban adult contemporary format (a term coined by Barry Mayo) usually attracts a large number of African Americans and sometimes Caucasian listeners through playing a great deal of R&B (without any form of rapping), gospel music, classic soul and dance music (including disco).
What demographic group is the urban adult contemporary format marketed to?
A: African Americans

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In 1968 Ronald Melzack and Kenneth Casey described pain in terms of its three dimensions: "sensory-discriminative" (sense of the intensity, location, quality and duration of the pain), "affective-motivational" (unpleasantness and urge to escape the unpleasantness), and "cognitive-evaluative" (cognitions such as appraisal, cultural values, distraction and hypnotic suggestion). They theorized that pain intensity (the sensory discriminative dimension) and unpleasantness (the affective-motivational dimension) are not simply determined by the magnitude of the painful stimulus, but "higher" cognitive activities can influence perceived intensity and unpleasantness. Cognitive activities "may affect both sensory and affective experience or they may modify primarily the affective-motivational dimension. Thus, excitement in games or war appears to block both dimensions of pain, while suggestion and placebos may modulate the affective-motivational dimension and leave the sensory-discriminative dimension relatively undisturbed." (p. 432) The paper ends with a call to action: "Pain can be treated not only by trying to cut down the sensory input by anesthetic block, surgical intervention and the like, but also by influencing the motivational-affective and cognitive factors as well." (p. 435)
The affective-motivational dimension of pain is characterized by what urge?
A: urge to escape the unpleasantness

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Horizontal gene transfer is invoked to explain how there is often extreme similarity between small portions of the genomes of two organisms that are otherwise very distantly related. Horizontal gene transfer seems to be common among many microbes. Also, eukaryotic cells seem to have experienced a transfer of some genetic material from their chloroplast and mitochondrial genomes to their nuclear chromosomes.
What helps explain why different parts of chloroplasts are similar?
A: unanswerable

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Nanjing is the transportation hub in eastern China and the downstream Yangtze River area. Different means of transportation constitute a three-dimensional transport system that includes land, water and air. As in most other Chinese cities, public transportation is the dominant mode of travel of the majority of the citizens. As of October 2014, Nanjing had five bridges and two tunnels over the Yangtze River, which are tying districts north of the river with the city centre on the south bank.
How many tunnels does Nanjing have over the Yangtze River?
A:
two