Problem: USB:

USB is a serial bus, using four shielded wires for the USB 2.0 variant: two for power (VBUS and GND), and two for differential data signals (labelled as D+ and D− in pinouts). Non-Return-to-Zero Inverted (NRZI) encoding scheme is used for transferring data, with a sync field to synchronize the host and receiver clocks. D+ and D− signals are transmitted on a twisted pair, providing half-duplex data transfers for USB 2.0. Mini and micro connectors have their GND connections moved from pin #4 to pin #5, while their pin #4 serves as an ID pin for the On-The-Go host/client identification.

What are the four shielded wires in the USB 2.0 variant used for?
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A: two for power (VBUS and GND), and two for differential data signals


Problem: Various American Idol alumni had success on various record charts around the world; in the U.S. they had achieved 345 number ones on the Billboard charts in its first ten years. According to Fred Bronson, author of books on the Billboard charts, no other entity has ever created as many hit-making artists and best-selling albums and singles. In 2007, American Idol alums accounted for 2.1% of all music sales. Its alumni have a massive impact on radio; in 2007, American Idol had become "a dominant force in radio" according to the president of the research company Mediabase which monitors radio stations Rich Meyer. By 2010, four winners each had more than a million radio spins, with Kelly Clarkson leading the field with over four million spins.
How many number one Billboard singles were released by American Idol contestants in the shows first decade? 
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Answer: 345


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In 1966, CBS reorganized its corporate structure with Leiberson promoted to head the new "CBS-Columbia Group" which made the now renamed CBS Records company a separate unit of this new group run by Clive Davis.
Leiberson was promoted to secretary for what group?
A: unanswerable


Context and question: Kinect is a "controller-free gaming and entertainment experience" for the Xbox 360. It was first announced on June 1, 2009 at the Electronic Entertainment Expo, under the codename, Project Natal. The add-on peripheral enables users to control and interact with the Xbox 360 without a game controller by using gestures, spoken commands and presented objects and images. The Kinect accessory is compatible with all Xbox 360 models, connecting to new models via a custom connector, and to older ones via a USB and mains power adapter. During their CES 2010 keynote speech, Robbie Bach and Microsoft CEO Steve Ballmer went on to say that Kinect will be released during the holiday period (November–January) and it will work with every 360 console. Its name and release date of 2010-11-04 were officially announced on 2010-06-13, prior to Microsoft's press conference at E3 2010.
When was Kinect first announced?
Answer: June 1, 2009


Question: The morphology of Catalan personal pronouns is complex, specially in unstressed forms, which are numerous (13 distinct forms, compared to 11 in Spanish or 9 in Italian).  Features include the gender-neutral ho and the great degree of freedom when combining different unstressed pronouns (65 combinations).
Is there an answer to this question: How many personal pronouns are there is Spanish?

Answer: 11


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Most types of capacitor include a dielectric spacer, which increases their capacitance. These dielectrics are most often insulators. However, low capacitance devices are available with a vacuum between their plates, which allows extremely high voltage operation and low losses. Variable capacitors with their plates open to the atmosphere were commonly used in radio tuning circuits. Later designs use polymer foil dielectric between the moving and stationary plates, with no significant air space between them.
How did the capacitor traditionally used in radio tuning circuits stay the same over time?
A:
unanswerable