[Q]: Extract the answer to the question from the following context. Question: Who did the Fighter Interception Unit and also Cunningham have to thank for being able to use the airborne radar? Context: Nevertheless, it was radar that proved to be critical weapon in the night battles over Britain from this point onward. Dowding had introduced the concept of airborne radar and encouraged its usage. Eventually it would become a success. On the night of 22/23 July 1940, Flying Officer Cyril Ashfield (pilot), Pilot Officer Geoffrey Morris (Observer) and Flight Sergeant Reginald Leyland (Air Intercept radar operator) of the Fighter Interception Unit became the first pilot and crew to intercept and destroy an enemy aircraft using onboard radar to guide them to a visual interception, when their AI night fighter brought down a Do 17 off Sussex. On 19 November 1940 the famous RAF night fighter ace John Cunningham shot down a Ju 88 bomber using airborne radar, just as Dowding had predicted.
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[A]: Dowding

[Q]: Extract the answer to the question from the following context. Question: __ was spread to Sierra Leone by Canadian missionaries. Context: Presbyterians distinguish themselves from other denominations by doctrine, institutional organization (or "church order") and worship; often using a "Book of Order" to regulate common practice and order. The origins of the Presbyterian churches are in Calvinism. Many branches of Presbyterianism are remnants of previous splits from larger groups. Some of the splits have been due to doctrinal controversy, while some have been caused by disagreement concerning the degree to which those ordained to church office should be required to agree with the Westminster Confession of Faith, which historically serves as an important confessional document second only to the Bible, yet directing particularities in the standardization and translation of the Bible in Presbyterian churches.
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[A]: Calvinism

[Q]: Extract the answer to the question from the following context. Question: What kind of company was Jerrold Electronics to American Cable Systems? Context: In 1963, Ralph J. Roberts in conjunction with his two business partners, Daniel Aaron and Julian A. Brodsky, purchased American Cable Systems as a corporate spin-off from its parent, Jerrold Electronics, for US $500,000. At the time, American Cable was a small cable operator in Tupelo, Mississippi, with five channels and 12,000 customers. Storecast Corporation of America, a product placement supermarket specialist marketing firm, was purchased by American Cable in 1965. With Storecast being a Muzak client, American Cable purchased its first Muzak franchise of many in Orlando, Florida.
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[A]: parent

[Q]: Extract the answer to the question from the following context. Question: What singing group was mentioned after The Beatles? Context: Towards the center, at the end of the groove, there is another wide-pitched section known as the lead-out. At the very end of this section the groove joins itself to form a complete circle, called the lock groove; when the stylus reaches this point, it circles repeatedly until lifted from the record. On some recordings (for example Sgt. Pepper's Lonely Hearts Club Band by The Beatles, Super Trouper by Abba and Atom Heart Mother by Pink Floyd), the sound continues on the lock groove, which gives a strange repeating effect. Automatic turntables rely on the position or angular velocity of the arm, as it reaches the wider spacing in the groove, to trigger a mechanism that lifts the arm off the record. Precisely because of this mechanism, most automatic turntables are incapable of playing any audio in the lock groove, since they will lift the arm before it reaches that groove.
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[A]:
Abba