Problem: Given the question: Question: "In what shape is the shaft?" Context: "A elevator of this kind uses a vacuum on top of the cab and a valve on the top of the "shaft" to move the cab upwards and closes the valve in order to keep the cab at the same level. a diaphragm or a piston is used as a "brake" if there's a sudden increase in pressure avove the cab. however, to go down, it opens the valve so that the air can pressurize the top of the "shaft", allowing the cab to go down by its own weight. this also means that in case of a power failure, the cab will automatically go down. the "shaft" is made of acrilic, is always round, due to the shape of the vacuum pump turbine. in order to keep the air inside of the cab, rubber seals are used. due to technical limitations, these elevators have a low capacity. they usually allow 1-3 passengers and up to 525 lbs." Answer:
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The answer is:
round

Problem: Given the question: Question: "What event spurred a difficult time for Beyonce?" Context: "LeToya Luckett and Roberson became unhappy with Mathew's managing of the band and eventually were replaced by Farrah Franklin and Michelle Williams. Beyonce experienced depression following the split with Luckett and Roberson after being publicly blamed by the media, critics, and blogs for its cause. Her long-standing boyfriend left her at this time. The depression was so severe it lasted for a couple of years, during which she occasionally kept herself in her bedroom for days and refused to eat anything. Beyonce stated that she struggled to speak about her depression because Destiny's Child had just won their first Grammy Award and she feared no one would take her seriously. Beyonce would later speak of her mother as the person who helped her fight it. Franklin was dismissed, leaving just Beyonce, Rowland, and Williams." Answer:
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The answer is:
the split with Luckett and Roberson

Problem: Given the question: Question: "Has Oklahoma City been struck by more F/EF4s or more F/EF5s?" Context: "Oklahoma City has a very active severe weather season from March through June, especially during April and May. Being in the center of what is colloquially referred to as Tornado Alley, it is prone to especially frequent and severe tornadoes, as well as very severe hailstorms and occasional derechoes. Tornadoes have occurred in every month of the year and a secondary smaller peak also occurs during autumn, especially October. The Oklahoma City metropolitan area is one of the most tornado-prone major cities in the world, with about 150 tornadoes striking within the city limits since 1890. Since the time weather records have been kept, Oklahoma City has been struck by thirteen violent tornadoes, eleven F/EF4s and two F/EF5. On May 3, 1999 parts of southern Oklahoma City and nearby suburban communities suffered from one of the most powerful tornadoes on record, an F5 on the Fujita scale, with wind speeds estimated by radar at 318 mph (510 km/h). On May 20, 2013, far southwest Oklahoma City, along with Newcastle and Moore, was hit again by a EF5 tornado; it was 0.5 to 1.3 miles (0.80 to 2.09 km) wide and killed 23 people. Less than two weeks later, on May 31, another outbreak affected the Oklahoma City area, including an EF1 and an EF0 within the city and a tornado several miles west of the city that was 2.6 miles (4.2 km) in width, the widest tornado ever recorded." Answer:
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The answer is:
F/EF4s