Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Lossy data compression is the converse of lossless data compression. In these schemes, some loss of information is acceptable. Dropping nonessential detail from the data source can save storage space. Lossy data compression schemes are designed by research on how people perceive the data in question. For example, the human eye is more sensitive to subtle variations in luminance than it is to the variations in color. JPEG image compression works in part by rounding off nonessential bits of information. There is a corresponding trade-off between preserving information and reducing size. A number of popular compression formats exploit these perceptual differences, including those used in music files, images, and video.
What is there a corresponding compression scheme between?
A: unanswerable

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The movement was pioneered by Georges Braque and Pablo Picasso, joined by Jean Metzinger, Albert Gleizes, Robert Delaunay, Henri Le Fauconnier, Fernand Leger and Juan Gris. A primary influence that led to Cubism was the representation of three-dimensional form in the late works of Paul Cezanne. A retrospective of Cezanne's paintings had been held at the Salon d'Automne of 1904, current works were displayed at the 1905 and 1906 Salon d'Automne, followed by two commemorative retrospectives after his death in 1907.
What movement did Picasso not participate in?
A: unanswerable

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By the late 1990s, blue LEDs became widely available. They have an active region consisting of one or more InGaN quantum wells sandwiched between thicker layers of GaN, called cladding layers. By varying the relative In/Ga fraction in the InGaN quantum wells, the light emission can in theory be varied from violet to amber. Aluminium gallium nitride (AlGaN) of varying Al/Ga fraction can be used to manufacture the cladding and quantum well layers for ultraviolet LEDs, but these devices have not yet reached the level of efficiency and technological maturity of InGaN/GaN blue/green devices. If un-alloyed GaN is used in this case to form the active quantum well layers, the device will emit near-ultraviolet light with a peak wavelength centred around 365 nm. Green LEDs manufactured from the InGaN/GaN system are far more efficient and brighter than green LEDs produced with non-nitride material systems, but practical devices still exhibit efficiency too low for high-brightness applications.[citation needed]
What LEDs are more efficient when produced from the InGaN/GaN systems than without?
A: Green

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Dell sells personal computers (PCs), servers, data storage devices, network switches, software, computer peripherals, HDTVs, cameras, printers, MP3 players, and electronics built by other manufacturers. The company is well known for its innovations in supply chain management and electronic commerce, particularly its direct-sales model and its "build-to-order" or "configure to order" approach to manufacturingdelivering individual PCs configured to customer specifications. Dell was a pure hardware vendor for much of its existence, but with the acquisition in 2009 of Perot Systems, Dell entered the market for IT services. The company has since made additional acquisitions in storage and networking systems, with the aim of expanding their portfolio from offering computers only to delivering complete solutions for enterprise customers.
For the minority of Dell's existence, what were they a vendor of?
A:
unanswerable