input question: Question: "At what point was the key river on the continent controlled?" Context: "The Byzantine Empire ruled the northern shores of the Sahara from the 5th to the 7th centuries. After the Muslim conquest of Arabia (Arabian peninsula) the Muslim conquest of North Africa began in the mid-7th to early 8th centuries, Islamic influence expanded rapidly on the Sahara. By the end of 641 all of Egypt was in Muslim hands. The trade across the desert intensified. A significant slave trade crossed the desert. It has been estimated that from the 10th to 19th centuries some 6,000 to 7,000 slaves were transported north each year." Answer:???
output answer: By the end of 641

Question: "How did Oklahoma's high chool graduate rate rank copanred ot its region" Context: "The state is among the best in pre-kindergarten education, and the National Institute for Early Education Research rated it first in the United States with regard to standards, quality, and access to pre-kindergarten education in 2004, calling it a model for early childhood schooling. High school dropout rate decreased from 3.1 to 2.5 percent between 2007 and 2008 with Oklahoma ranked among 18 other states with 3 percent or less dropout rate. In 2004, the state ranked 36th in the nation for the relative number of adults with high school diplomas, though at 85.2 percent, it had the highest rate among southern states." Answer:
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Answer: had the highest rate among southern states

Q: Question: "__ relied heavily on reinforced concrete." Context: "The library is based at two public sites: the Reading Room at the RIBA's headquarters, 66 Portland Place, London; and the RIBA Architecture Study Rooms in the Henry Cole Wing of the V&A. The Reading Room, designed by the building's architect George Grey Wornum and his wife Miriam, retains its original 1934 Art Deco interior with open bookshelves, original furniture and double-height central space. The study rooms, opened in 2004, were designed by Wright & Wright. The library is funded entirely by the RIBA but it is open to the public without charge. It operates a free education programme aimed at students, education groups and families, and an information service for RIBA members and the public through the RIBA Information Centre." Answer:
A: Art Deco

Question: Question: "Which resolution format was implemented first: 8K or 4K?" Context: "In November 2008, 720p HD support was added. At the time of the 720p launch, the YouTube player was changed from a 4:3 aspect ratio to a widescreen 16:9. With this new feature, YouTube began a switchover to H.264/MPEG-4 AVC as its default video compression format. In November 2009, 1080p HD support was added. In July 2010, YouTube announced that it had launched a range of videos in 4K format, which allows a resolution of up to 40963072 pixels. In June 2015, support for 8K resolution was added, with the videos playing at 76804320 pixels." Answer:
Answer: 4K

[Q]: Question: "Whose pioneering work was released after 1930, but before 1951?" Context: "Emotions are thought to be related to certain activities in brain areas that direct our attention, motivate our behavior, and determine the significance of what is going on around us. Pioneering work by Broca (1878), Papez (1937), and MacLean (1952) suggested that emotion is related to a group of structures in the center of the brain called the limbic system, which includes the hypothalamus, cingulate cortex, hippocampi, and other structures. More recent research has shown that some of these limbic structures are not as directly related to emotion as others are while some non-limbic structures have been found to be of greater emotional relevance." Answer:
****
[A]: Papez

Problem: Given the question: Question: "What causes the most sound quality problems?" Context: "Due to recording mastering and manufacturing limitations, both high and low frequencies were removed from the first recorded signals by various formulae. With low frequencies, the stylus must swing a long way from side to side, requiring the groove to be wide, taking up more space and limiting the playing time of the record. At high frequencies, hiss, pops, and ticks are significant. These problems can be reduced by using equalization to an agreed standard. During recording the amplitude of low frequencies is reduced, thus reducing the groove width required, and the amplitude at high frequencies is increased. The playback equipment boosts bass and cuts treble so as to restore the tonal balance in the original signal; this also reduces the high frequency noise. Thus more music will fit on the record, and noise is reduced." Answer:
++++++++++++++++++++++++++++++++
The answer is:
high frequencies