Problem: Canadian football:

During the last three minutes of a half, the penalty for failure to place the ball in play within the 20-second play clock, known as "time count" (this foul is known as "delay of game" in American football), is dramatically different from during the first 27 minutes. Instead of the penalty being 5 yards with the down repeated, the base penalty (except during convert attempts) becomes loss of down on first or second down, and 10 yards on third down with the down repeated. In addition, as noted previously, the referee can give possession to the defence for repeated deliberate time count violations on third down.

How many yards does the offense lose for a time count on third down?
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A: 10


Problem: DC systems (especially third-rail systems) are limited to relatively low voltages and this can limit the size and speed of trains and cannot use low-level platform and also limit the amount of air-conditioning that the trains can provide. This may be a factor favouring overhead wires and high-voltage AC, even for urban usage. In practice, the top speed of trains on third-rail systems is limited to 100 mph (160 km/h) because above that speed reliable contact between the shoe and the rail cannot be maintained.
Can DC systems use low-level platform?
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Answer: cannot


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The Feinberg School of Medicine (previously the Northwestern University Medical School) has produced a number of notable graduates, including Mary Harris Thompson, Class of 1870, ad eundem, first female surgeon in Chicago, first female surgeon at Cook County Hospital, and founder of the Mary Thomson Hospital, Roswell Park, Class of 1876, prominent surgeon for whom the Roswell Park Cancer Institute in Buffalo, New York, is named, Daniel Hale Williams, Class of 1883, performed the first successful American open heart surgery; only black charter member of the American College of Surgeons, Charles Horace Mayo, Class of 1888, co-founder of Mayo Clinic, Carlos Montezuma, Class of 1889, one of the first Native Americans to receive a Doctor of Medicine degree from any school, and founder of the Society of American Indians, Howard T. Ricketts, Class of 1897, who discovered bacteria of the genus Rickettsia, and identified the cause and methods of transmission of rocky mountain spotted fever, Allen B. Kanavel, Class of 1899, founder, regent, and president of the American College of Surgeons, internationally recognized as founder of modern hand and peripheral nerve surgery, Robert F. Furchgott, Class of 1940, received a Lasker Award in 1996 and the 1998 Nobel Prize in Physiology or Medicine for his co-discovery of nitric oxide, Thomas E. Starzl, Class of 1952, performed the first successful liver transplant in 1967 and received the National Medal of Science in 2004 and a Lasker Award in 2012, Joseph P. Kerwin, first physician in space, flew on three skylab missions and later served as director of Space and Life Sciences at NASA, C. Richard Schlegel, Class of 1972, developed the dominant patent for a vaccine against human papillomavirus (administered as Gardasil) to prevent cervical cancer, David J. Skorton, Class of 1974, a noted cardiologist became president of Cornell University in 2006, and Andrew E. Senyei, Class of 1979, inventor, venture capitalist, and entrepreneur, founder of biotech and genetics companies, and a university trustee.
Which graduate of The Feinburg School of Medicine co-founded the Mayo Clinic?
A: Charles Horace Mayo


Context and question: Constantius, renewing his previous policies favoring the Arians, banished Athanasius from Alexandria once again. This was followed, in 356, by an attempt to arrest Athanasius during a vigil service. Athanasius fled to Upper Egypt, where he stayed in several monasteries and other houses. During this period, Athanasius completed his work Four Orations against the Arians and defended his own recent conduct in the Apology to Constantius and Apology for His Flight. Constantius's persistence in his opposition to Athanasius, combined with reports Athanasius received about the persecution of non-Arians by the new Arian bishop George of Laodicea, prompted Athanasius to write his more emotional History of the Arians, in which he described Constantius as a precursor of the Antichrist.
In which work did he refer to Constantius as a precursor of the Antichrist?
Answer: History of the Arians


Question: From the 4th century, the Empire's Balkan territories, including Greece, suffered from the dislocation of the Barbarian Invasions. The raids and devastation of the Goths and Huns in the 4th and 5th centuries and the Slavic invasion of Greece in the 7th century resulted in a dramatic collapse in imperial authority in the Greek peninsula. Following the Slavic invasion, the imperial government retained formal control of only the islands and coastal areas, particularly the densely populated walled cities such as Athens, Corinth and Thessalonica, while some mountainous areas in the interior held out on their own and continued to recognize imperial authority. Outside of these areas, a limited amount of Slavic settlement is generally thought to have occurred, although on a much smaller scale than previously thought.
Is there an answer to this question: When did the Slavs invade Greece?

Answer: 7th century


Problem: Republic of the Congo:

Before the 1997 war, about 9,000 Europeans and other non-Africans lived in Congo, most of whom were French; only a fraction of this number remains. Around 300 American expatriates reside in the Congo.

Prior to the civil war in '97, how many non-Africans lived in the Republic of the Congo?
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A:
about 9,000