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: What does the S in "PBS" stand for?, Context: New York is also a major center for non-commercial educational media. The oldest public-access television channel in the United States is the Manhattan Neighborhood Network, founded in 1971. WNET is the city's major public television station and a primary source of national Public Broadcasting Service (PBS) television programming. WNYC, a public radio station owned by the city until 1997, has the largest public radio audience in the United States.

Answer: Service


Question: How do supercapacitors store energy?, Context: Last but not least the electric double-layer capacitor (now Supercapacitors) were invented. In 1957 H. Becker developed a "Low voltage electrolytic capacitor with porous carbon electrodes". He believed that the energy was stored as a charge in the carbon pores used in his capacitor as in the pores of the etched foils of electrolytic capacitors. Because the double layer mechanism was not known by him at the time, he wrote in the patent: "It is not known exactly what is taking place in the component if it is used for energy storage, but it leads to an extremely high capacity.".

Answer:
the double layer mechanism