Here is a question about this article: Recent developments in LEDs permit them to be used in environmental and task lighting. LEDs have many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved physical robustness, smaller size, and faster switching. Light-emitting diodes are now used in applications as diverse as aviation lighting, automotive headlamps, advertising, general lighting, traffic signals, camera flashes and lighted wallpaper. As of 2015[update], LEDs powerful enough for room lighting remain somewhat more expensive, and require more precise current and heat management, than compact fluorescent lamp sources of comparable output.
What is the answer to this question: What is an advantage to using LED lighting over the normal light sources?
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So... longer lifetime

Here is a question about this article: When comparing different documents, or "witnesses", of a single, original text, the observed differences are called variant readings, or simply variants or readings. It is not always apparent which single variant represents the author's original work. The process of textual criticism seeks to explain how each variant may have entered the text, either by accident (duplication or omission) or intention (harmonization or censorship), as scribes or supervisors transmitted the original author's text by copying it. The textual critic's task, therefore, is to sort through the variants, eliminating those most likely to be un-original, hence establishing a "critical text", or critical edition, that is intended to best approximate the original. At the same time, the critical text should document variant readings, so the relation of extant witnesses to the reconstructed original is apparent to a reader of the critical edition. In establishing the critical text, the textual critic considers both "external" evidence (the age, provenance, and affiliation of each witness) and "internal" or "physical" considerations (what the author and scribes, or printers, were likely to have done).
What is the answer to this question: As well as representing the original text, a critical text must also do what?
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So... document variant readings

Here is a question about this article: The official introduction of the metric system in September 1799 was unpopular in large sections of French society. Napoleon's rule greatly aided adoption of the new standard not only across France but also across the French sphere of influence. Napoleon ultimately took a retrograde step in 1812 when he passed legislation to introduce the mesures usuelles (traditional units of measurement) for retail tradea system of measure that resembled the pre-revolutionary units but were based on the kilogram and the metre; for example the livre metrique (metric pound) was 500 g instead of 489.5 gthe value of the livre du roi (the king's pound). Other units of measure were rounded in a similar manner. This however laid the foundations for the definitive introduction of the metric system across Europe in the middle of the 19th century.
What is the answer to this question: What year did Napoleon pass legislation that introduced traditional units of measurement for retail trade?
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So...
1812