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Initially sensors were optical and acoustic devices developed during the First World War and continued into the 1930s, but were quickly superseded by radar, which in turn was supplemented by optronics in the 1980s. Command and control remained primitive until the late 1930s, when Britain created an integrated system for ADGB that linked the ground-based air defence of the army's AA Command, although field-deployed air defence relied on less sophisticated arrangements. NATO later called these arrangements an "air defence ground environment", defined as "the network of ground radar sites and command and control centres within a specific theatre of operations which are used for the tactical control of air defence operations".

Radar was supplemented by what in the 1980s?
Answer: optronics
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In 2009, IGN named the Xbox 360 the sixth-greatest video game console of all time, out of a field of 25. Although not the best-selling console of the seventh-generation, the Xbox 360 was deemed by TechRadar to be the most influential, by emphasizing digital media distribution and online gaming through Xbox Live, and by popularizing game achievement awards. PC Magazine considered the Xbox 360 the prototype for online gaming as it "proved that online gaming communities could thrive in the console space". Five years after the Xbox 360's original debut, the well-received Kinect motion capture camera was released, which set the record of being the fastest selling consumer electronic device in history, and extended the life of the console. Edge ranked Xbox 360 the second-best console of the 19932013 period, stating "It had its own social network, cross-game chat, new indie games every week, and the best version of just about every multiformat game...Killzone is no Halo and nowadays Gran Turismo is no Forza, but it's not about the exclusivesthere's nothing to trump Naughty Dog's PS3 output, after all. Rather, it's about the choices Microsoft made back in the original Xbox's lifetime. The PC-like architecture meant those early EA Sports titles ran at 60fps compared to only 30 on PS3, Xbox Live meant every dedicated player had an existing friends list, and Halo meant Microsoft had the killer next-generation exclusive. And when developers demo games on PC now they do it with a 360 padanother industry benchmark, and a critical one."

What 360 peripheral was the fastest selling consumer electronic device in history?
Answer: Kinect
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Beneath the plain lies the Biscayne Aquifer, a natural underground source of fresh water that extends from southern Palm Beach County to Florida Bay, with its highest point peaking around the cities of Miami Springs and Hialeah. Most of the Miami metropolitan area obtains its drinking water from this aquifer. As a result of the aquifer, it is not possible to dig more than 15 to 20 ft (5 to 6 m) beneath the city without hitting water, which impedes underground construction, though some underground parking garages exist. For this reason, the mass transit systems in and around Miami are elevated or at-grade.[citation needed]

After digging how many meters is one sure to reach running water in Miami?
Answer:
5 to 6