QUES: 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 does AlGaN stand for?

ANS: Aluminium gallium nitride

QUES: A very high resolution source may require more bandwidth than available in order to be transmitted without loss of fidelity. The lossy compression that is used in all digital HDTV storage and transmission systems will distort the received picture, when compared to the uncompressed source.
The compression used in all SDTV storage and transmission systems will do what if resolution is too high?

ANS: unanswerable

QUES: This period also saw some contacts with Jesuits and Capuchins from Europe, and in 1774 a Scottish nobleman, George Bogle, came to Shigatse to investigate prospects of trade for the British East India Company. However, in the 19th century the situation of foreigners in Tibet grew more tenuous. The British Empire was encroaching from northern India into the Himalayas, the Emirate of Afghanistan and the Russian Empire were expanding into Central Asia and each power became suspicious of the others' intentions in Tibet.
Who came to Tibet from Europe?

ANS: Jesuits and Capuchins

QUES: The Universal Film Manufacturing Company was incorporated in New York on April 30, 1912. Laemmle, who emerged as president in July 1912, was the primary figure in the partnership with Dintenfass, Baumann, Kessel, Powers, Swanson, Horsley, and Brulatour. Eventually all would be bought out by Laemmle. The new Universal studio was a vertically integrated company, with movie production, distribution and exhibition venues all linked in the same corporate entity, the central element of the Studio system era.
Along with exhibition and distribution, what business did the Universal Film Manufacturing Company engage in?

ANS:
movie production