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.

Q: Passage: The most frequent musical contributor during the first 15 years was Dudley Simpson, who is also well known for his theme and incidental music for Blake's 7, and for his haunting theme music and score for the original 1970s version of The Tomorrow People. Simpson's first Doctor Who score was Planet of Giants (1964) and he went on to write music for many adventures of the 1960s and 1970s, including most of the stories of the Jon Pertwee/Tom Baker periods, ending with The Horns of Nimon (1979). He also made a cameo appearance in The Talons of Weng-Chiang (as a Music hall conductor). Question: In what decades was Dudley Simpson most active in contributing to Doctor Who?

A: the 1960s and 1970s
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Q: Passage: Between Bingen and Bonn, the Middle Rhine flows through the Rhine Gorge, a formation which was created by erosion. The rate of erosion equaled the uplift in the region, such that the river was left at about its original level while the surrounding lands raised. The gorge is quite deep and is the stretch of the river which is known for its many castles and vineyards. It is a UNESCO World Heritage Site (2002) and known as 'the Romantic Rhine', with more than 40 castles and fortresses from the Middle Ages and many quaint and lovely country villages. Question: What gorge is between the Bingen and Bonn?

A: Rhine Gorge
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Q: Passage: Grissom, White, and Chaffee decided to name their flight Apollo 1 as a motivational focus on the first manned flight. They trained and conducted tests of their spacecraft at North American, and in the altitude chamber at the Kennedy Space Center. A 'plugs-out' test was planned for January, which would simulate a launch countdown on LC-34 with the spacecraft transferring from pad-supplied to internal power. If successful, this would be followed by a more rigorous countdown simulation test closer to the February 21 launch, with both spacecraft and launch vehicle fueled. Question: What was a plugs-out test done to simulate on the LC-34?

A:
launch countdown
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