Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In 2014 artist Jack White sold 40,000 copies of his second solo release, Lazaretto, on vinyl. The sales of the record beat the largest sales in one week on vinyl since 1991. The sales record was previously held by Pearl Jam's, Vitalogy, which sold 34,000 copies in one week in 1994. In 2014, the sale of vinyl records was the only physical music medium with increasing sales with relation to the previous year. Sales of other mediums including individual digital tracks, digital albums and compact discs have fallen, the latter having the greatest drop-in-sales rate.
What was unique to vinyl sales in 2014?
A: was the only physical music medium with increasing sales with relation to the previous year

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During encoding, 576 time-domain samples are taken and are transformed to 576 frequency-domain samples.[clarification needed] If there is a transient, 192 samples are taken instead of 576. This is done to limit the temporal spread of quantization noise accompanying the transient. (See psychoacoustics.)
How many domain samples are taken during encoding?
A: 576

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Film speed is used in the exposure equations to find the appropriate exposure parameters. Four variables are available to the photographer to obtain the desired effect: lighting, film speed, f-number (aperture size), and shutter speed (exposure time). The equation may be expressed as ratios, or, by taking the logarithm (base 2) of both sides, by addition, using the APEX system, in which every increment of 1 is a doubling of exposure; this increment is commonly known as a "stop". The effective f-number is proportional to the ratio between the lens focal length and aperture diameter, the diameter itself being proportional to the square root of the aperture area. Thus, a lens set to f/1.4 allows twice as much light to strike the focal plane as a lens set to f/2. Therefore, each f-number factor of the square root of two (approximately 1.4) is also a stop, so lenses are typically marked in that progression: f/1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32, etc.
What variables help the photographer produce the desired effect?
A: lighting, film speed, f-number (aperture size), and shutter speed (exposure time)

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Jehovah's Witnesses are perhaps best known for their efforts to spread their beliefs, most notably by visiting people from house to house, distributing literature published by the Watch Tower Society in 700 languages. The objective is to start a regular "Bible study" with any person who is not already a member, with the intention that the student be baptized as a member of the group; Witnesses are advised to consider discontinuing Bible studies with students who show no interest in becoming members. Witnesses are taught they are under a biblical command to engage in public preaching. They are instructed to devote as much time as possible to their ministry and are required to submit an individual monthly "Field Service Report". Baptized members who fail to report a month of preaching are termed "irregular" and may be counseled by elders; those who do not submit reports for six consecutive months are termed "inactive".
How many doors does the average Jehovah's Witnesses knock on each month?
A:
unanswerable