The problem: Answer a question about this article:
LED lamps have been advocated as the newest and best environmental lighting method. According to the Energy Saving Trust, LED lamps use only 10% power compared to a standard incandescent bulb, where compact fluorescent lamps use 20% and energy saving halogen lamps 70%. The lifetime is also much longer up to 50,000 hours. A downside is still the initial cost, which is higher than that of compact fluorescent lamps.
How much power does a halogen lamp save compared to a standard blub?
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The answer: 70%

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Although Greg argued that an editor should be free to use his judgment to choose between competing substantive readings, he suggested that an editor should defer to the copy-text when "the claims of two readings ... appear to be exactly balanced. ... In such a case, while there can be no logical reason for giving preference to the copy-text, in practice, if there is no reason for altering its reading, the obvious thing seems to be to let it stand." The "exactly balanced" variants are said to be indifferent.
What should one do when two readings are contradictory but balanced?
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The answer: if there is no reason for altering its reading, the obvious thing seems to be to let it stand.

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The art of mechanical analog computing reached its zenith with the differential analyzer, built by H. L. Hazen and Vannevar Bush at MIT starting in 1927. This built on the mechanical integrators of James Thomson and the torque amplifiers invented by H. W. Nieman. A dozen of these devices were built before their obsolescence became obvious.
The torque amplifiers of the differential analyzer were created by whom?
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The answer: H. W. Nieman

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More complex inflection is still found in certain lexicalized expressions like de heer des huizes (literally, the man of the house), etc. These are usually remnants of cases (in this instance, the genitive case which is still used in German, cf. Der Herr des Hauses) and other inflections no longer in general use today. In such lexicalized expressions remnants of strong and weak nouns can be found too, e.g. in het jaar des Heren (Anno Domini), where "-en" is actually the genitive ending of the weak noun. Also in this case, German retains this feature. Though the genitive is widely avoided in speech.
What case no longer used in Dutch is still present in German phrases like "Der Herr des Hauses"?
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The answer:
genitive