Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In addition to Old Persian and Avestan, which are the only directly attested Old Iranian languages, all Middle Iranian languages must have had a predecessor "Old Iranian" form of that language, and thus can all be said to have had an (at least hypothetical) "Old" form. Such hypothetical Old Iranian languages include Carduchi (the hypothetical predecessor to Kurdish) and Old Parthian. Additionally, the existence of unattested languages can sometimes be inferred from the impact they had on neighbouring languages. Such transfer is known to have occurred for Old Persian, which has (what is called) a "Median" substrate in some of its vocabulary. Also, foreign references to languages can also provide a hint to the existence of otherwise unattested languages, for example through toponyms/ethnonyms or in the recording of vocabulary, as Herodotus did for what he called "Scythian".
Who reported vocabulary for old Persian?
A: unanswerable

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A wireless Internet service provider (WISP) is an Internet service provider with a network based on wireless networking. Technology may include commonplace Wi-Fi wireless mesh networking, or proprietary equipment designed to operate over open 900 MHz, 2.4 GHz, 4.9, 5.2, 5.4, 5.7, and 5.8 GHz bands or licensed frequencies such as 2.5 GHz (EBS/BRS), 3.65 GHz (NN) and in the UHF band (including the MMDS frequency band) and LMDS.[citation needed]
What are some bands that Wi-Fi can operate over? 
A: 900 MHz, 2.4 GHz, 4.9, 5.2, 5.4, 5.7, and 5.8 GHz bands

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There are two levels of service provided — a free service to civilians and licensed service to the Chinese government and military. The free civilian service has a 10-meter location-tracking accuracy, synchronizes clocks with an accuracy of 10 nanoseconds, and measures speeds to within 0.2 m/s. The restricted military service has a location accuracy of 10 centimetres, can be used for communication, and will supply information about the system status to the user. To date, the military service has been granted only to the People's Liberation Army and to the Military of Pakistan.
The paid civilian service has a location tracking accuracy of how many meters?
A: unanswerable

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According to the Office for National Statistics, at the 2001 census there were over a million black people in the United Kingdom; 1% of the total population described themselves as "Black Caribbean", 0.8% as "Black African", and 0.2% as "Black other". Britain encouraged the immigration of workers from the Caribbean after World War II; the first symbolic movement was those who came on the ship the Empire Windrush. The preferred official umbrella term is "black and minority ethnic" (BME), but sometimes the term "black" is used on its own, to express unified opposition to racism, as in the Southall Black Sisters, which started with a mainly British Asian constituency, and the National Black Police Association, which has a membership of "African, African-Caribbean and Asian origin".
In 2001 how many black people lived in the UK?
A:
over a million black