The problem: Answer a question about this article:
The question of priority for the variable resistance feature of the telephone was raised by the examiner before he approved Bell's patent application. He told Bell that his claim for the variable resistance feature was also described in Gray's caveat. Bell pointed to a variable resistance device in Bell's previous application in which Bell described a cup of mercury, not water. Bell had filed the mercury application at the patent office a year earlier on February 25, 1875, long before Elisha Gray described the water device. In addition, Gray abandoned his caveat, and because he did not contest Bell's priority, the examiner approved Bell's patent on March 3, 1876. Gray had reinvented the variable resistance telephone, but Bell was the first to write down the idea and the first to test it in a telephone.
When did Bell put in his prior patent?
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The answer: February 25, 1875

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George Sarton, the author of The History of Science, described Ibn Sina as "one of the greatest thinkers and medical scholars in history" and called him "the most famous scientist of Islam and one of the most famous of all races, places, and times." He was one of the Islamic world's leading writers in the field of medicine. Along with Rhazes, Abulcasis, Ibn al-Nafis, and al-Ibadi, Ibn Sina is considered an important compiler of early Muslim medicine. He is remembered in the Western history of medicine as a major historical figure who made important contributions to medicine and the European Renaissance. His medical texts were unusual in that where controversy existed between Galen and Aristotle's views on medical matters (such as anatomy), he preferred to side with Aristotle, where necessary updating Aristotle's position to take into account post-Aristotelian advances in anatomical knowledge. Aristotle's dominant intellectual influence among medieval European scholars meant that Avicenna's linking of Galen's medical writings with Aristotle's philosophical writings in the Canon of Medicine (along with its comprehensive and logical organisation of knowledge) significantly increased Avicenna's importance in medieval Europe in comparison to other Islamic writers on medicine. His influence following translation of the Canon was such that from the early fourteenth to the mid-sixteenth centuries he was ranked with Hippocrates and Galen as one of the acknowledged authorities, princeps medicorum ("prince of physicians").
Who said that Ibn Sina was one of the greatest thinkers?
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The answer: George Sarton

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US troops participated in a UN peacekeeping mission in Somalia beginning in 1992. By 1993 the US troops were augmented with Rangers and special forces with the aim of capturing warlord Mohamed Farrah Aidid, whose forces had massacred peacekeepers from Pakistan. During a raid in downtown Mogadishu, US troops became trapped overnight by a general uprising in the Battle of Mogadishu. Eighteen American soldiers were killed, and a US television crew filmed graphic images of the body of one soldier being dragged through the streets by an angry mob. Somali guerrillas paid a staggering toll at an estimated 1,0005,000 total casualties during the conflict. After much public disapproval, American forces were quickly withdrawn by President Bill Clinton. The incident profoundly affected US thinking about peacekeeping and intervention. The book Black Hawk Down was written about the battle, and was the basis for the later movie of the same name.
What was the name of the Somalian warlord who directed massacres of peacekeeping troops?
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The answer: Mohamed Farrah Aidid

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The astronomer Aristarchus of Samos was the first known person to propose a heliocentric model of the solar system, while the geographer Eratosthenes accurately calculated the circumference of the Earth. Hipparchus (c. 190 c. 120 BC) produced the first systematic star catalog. The level of achievement in Hellenistic astronomy and engineering is impressively shown by the Antikythera mechanism (150-100 BC), an analog computer for calculating the position of planets. Technological artifacts of similar complexity did not reappear until the 14th century, when mechanical astronomical clocks appeared in Europe.
What was used to determine the position of planets within the solar system?
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The answer:
the Antikythera mechanism