Answer the question from the given passage. Your answer should be directly extracted from the passage, and it should be a single entity, name, or number, not a sentence.

[EX Q]: Passage: The first recorded settlement in what is now Newcastle was Pons Aelius, a Roman fort and bridge across the River Tyne. It was given the family name of the Roman Emperor Hadrian, who founded it in the 2nd century AD. This rare honour suggests that Hadrian may have visited the site and instituted the bridge on his tour of Britain. The population of Pons Aelius at this period was estimated at 2,000. Fragments of Hadrian's Wall are still visible in parts of Newcastle, particularly along the West Road. The course of the 'Roman Wall' can be traced eastwards to the Segedunum Roman fort in Wallsend—the 'wall's end'—and to the supply fort Arbeia in South Shields. The extent of Hadrian's Wall was 73 miles (117 km), spanning the width of Britain; the Wall incorporated the Vallum, a large rearward ditch with parallel mounds, and was constructed primarily for defence, to prevent unwanted immigration and the incursion of Pictish tribes from the north, not as a fighting line for a major invasion. Question: What was the first recorded settlement in what became Newcastle?
[EX A]: Pons Aelius

[EX Q]: Passage: Oxygen was discovered independently by Carl Wilhelm Scheele, in Uppsala, in 1773 or earlier, and Joseph Priestley in Wiltshire, in 1774, but Priestley is often given priority because his work was published first. The name oxygen was coined in 1777 by Antoine Lavoisier, whose experiments with oxygen helped to discredit the then-popular phlogiston theory of combustion and corrosion. Its name derives from the Greek roots ὀξύς oxys, 'acid', literally 'sharp', referring to the sour taste of acids and -γενής -genes, 'producer', literally 'begetter', because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition. Common uses of oxygen includes the production cycle of steel, plastics and textiles, brazing, welding and cutting of steels and other metals, rocket propellant, in oxygen therapy and life support systems in aircraft, submarines, spaceflight and diving. Question: What previous work did Lavoisier experiments discredit?
[EX A]: phlogiston theory of combustion and corrosion

[EX Q]: Passage: The invasions of Baghdad, Samarkand, Urgench, Kiev, Vladimir among others caused mass murders, such as when portions of southern Khuzestan were completely destroyed. His descendant Hulagu Khan destroyed much of Iran's northern part and sacked Baghdad although his forces were halted by the Mamluks of Egypt, but Hulagu's descendant Ghazan Khan would return to beat the Egyptian Mamluks right out of Levant, Palestine and even Gaza. According to the works of the Persian historian Rashid-al-Din Hamadani, the Mongols killed more than 70,000 people in Merv and more than 190,000 in Nishapur. In 1237 Batu Khan, a grandson of Genghis Khan, launched an invasion into Kievan Rus'. Over the course of three years, the Mongols destroyed and annihilated all of the major cities of Eastern Europe with the exceptions of Novgorod and Pskov. Question: In which year did Genghis Khan's grandson invade Kievan Rus'?
[EX A]:
1237