The problem: Answer a question about this article:
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?
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The answer: Green

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A further complication is that the measurement of p involves the measurement of an electric current: this is invariably measured in conventional amperes rather than in SI amperes, so a conversion factor is required. The symbol p-90 is used for the measured gyromagnetic ratio using conventional electrical units. In addition, there are two methods of measuring the value, a "low-field" method and a "high-field" method, and the conversion factors are different in the two cases. Only the high-field value p-90(hi) is of interest in determining the Planck constant.
Why is the measurement of electric current an issue in the estimate of the gyromagnetic ratio?
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The answer: electric current: this is invariably measured in conventional amperes rather than in SI amperes

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The evidence of the early texts suggests that Siddhartha Gautama was born in a community that was on the periphery, both geographically and culturally, of the northeastern Indian subcontinent in the fifth century BCE. It was either a small republic, in which case his father was an elected chieftain, or an oligarchy, in which case his father was an oligarch.
According to early texts, when was Siddhartha Gautama born?
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The answer: fifth century BCE

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During the rule of the succeeding Hanoverian dynasty, power was gradually exercised more by parliament and the government. The first Hanoverian monarch, George I, relied on his ministers to a greater extent than did previous monarchs. Later Hanoverian monarchs attempted to restore royal control over legislation: George III and George IV both openly opposed Catholic Emancipation and asserted that to grant assent to a Catholic emancipation bill would violate the Coronation Oath, which required the sovereign to preserve and protect the established Church of England from Papal domination and would grant rights to individuals who were in league with a foreign power which did not recognise their legitimacy. However, George IV reluctantly granted his assent upon the advice of his ministers. Thus, as the concept of ministerial responsibility has evolved, the power to withhold royal assent has fallen into disuse, both in the United Kingdom and in the other Commonwealth realms.
Which monarch relied on his ministers more than any of his predecessors?
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The answer:
George I