Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Excavations in and near Agordat in central Eritrea yielded the remains of an ancient pre-Aksumite civilization known as the Gash Group. Ceramics were discovered that were related to those of the C-Group (Temehu) pastoral culture, which inhabited the Nile Valley between 25001500 BC. Some sources dating back to 3500 BC. Shards akin to those of the Kerma culture, another community that flourished in the Nile Valley around the same period, were also found at other local archaeological sites in the Barka valley belonging to the Gash Group. According to Peter Behrens (1981) and Marianne Bechaus-Gerst (2000), linguistic evidence indicates that the C-Group and Kerma peoples spoke Afroasiatic languages of the Berber and Cushitic branches, respectively.
When can the Berber be dated back to?
A: unanswerable

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Public schools in Raleigh are operated by the Wake County Public School System. Observers have praised the Wake County Public School System for its innovative efforts to maintain a socially, economically and racial balanced system by using income as a prime factor in assigning students to schools. Raleigh is home to three magnet high schools and three high schools offering the International Baccalaureate program. There are four early college high schools in Raleigh. Raleigh also has two alternative high schools.
What is the school system praised for?
A: innovative efforts to maintain a socially, economically and racial balanced system

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Historically, migration has been recorded as much as 3,000 years ago by Ancient Greek authors including Homer and Aristotle, and in the Book of Job, for species such as storks, turtle doves, and swallows. More recently, Johannes Leche began recording dates of arrivals of spring migrants in Finland in 1749, and scientific studies have used techniques including bird ringing and satellite tracking. Threats to migratory birds have grown with habitat destruction especially of stopover and wintering sites, as well as structures such as power lines and wind farms.
What is a major threat to migratory birds?
A: habitat destruction

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Currently, the Regular Force component of the Army consists of three field-ready brigade groups: 1 Canadian Mechanized Brigade Group, at CFB Edmonton and CFB Shilo; 2 Canadian Mechanized Brigade Group, at CFB Petawawa and CFB Gagetown; and 5 Canadian Mechanized Brigade Group, at CFB Valcartier and Quebec City. Each contains one regiment each of artillery, armour, and combat engineers, three battalions of infantry (all scaled in the British fashion), one battalion for logistics, a squadron for headquarters/signals, and several smaller support organizations. A tactical helicopter squadron and a field ambulance are co-located with each brigade, but do not form part of the brigade's command structure.
What squadron is present but is an official part of the Brigade?
A:
unanswerable