In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
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Question: What feature of airports was significantly increased in length to deal with the increase in jet aircraft traffic?, Context: Airport construction boomed during the 1960s with the increase in jet aircraft traffic. Runways were extended out to 3,000 m (9,800 ft). The fields were constructed out of reinforced concrete using a slip-form machine that produces a continual slab with no disruptions along the length. The early 1960s also saw the introduction of jet bridge systems to modern airport terminals, an innovation which eliminated outdoor passenger boarding. These systems became commonplace in the United States by the 1970s.

Answer: Runways


Question: Small pneumatic __ can hold only one person., Context: A residential elevator is often permitted to be of lower cost and complexity than full commercial elevators. They may have unique design characteristics suited for home furnishings, such as hinged wooden shaft-access doors rather than the typical metal sliding doors of commercial elevators. Construction may be less robust than in commercial designs with shorter maintenance periods, but safety systems such as locks on shaft access doors, fall arrestors, and emergency phones must still be present in the event of malfunction.

Answer: elevators


Question: Which source provided the smallest number of protesters?, Context: On the next day, December 18, protests turned into civil unrest as clashes between troops, volunteers, militia units, and Kazakh students turned into a wide-scale confrontation. The clashes could only be controlled on the third day. The Almaty events were followed by smaller protests and demonstrations in Shymkent, Pavlodar, Karaganda, and Taldykorgan. Reports from Kazakh SSR authorities estimated that the riots drew 3,000 people. Other estimates are of at least 30,000 to 40,000 protestors with 5,000 arrested and jailed, and an unknown number of casualties. Jeltoqsan leaders say over 60,000 Kazakhs participated in the protests. According to the Kazakh SSR government, there were two deaths during the riots, including a volunteer police worker and a student. Both of them had died due to blows to the head. About 100 others were detained and several others were sentenced to terms in labor camps. Sources cited by the Library of Congress claimed that at least 200 people died or were summarily executed soon thereafter; some accounts estimate casualties at more than 1,000. The writer Mukhtar Shakhanov claimed that a KGB officer testified that 168 protesters were killed, but that figure remains unconfirmed.

Answer:
Kazakh SSR authorities