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 is beneficial to London's economy?, Context: London is one of the leading tourist destinations in the world and in 2015 was ranked as the most visited city in the world with over 65 million visits. It is also the top city in the world by visitor cross-border spending, estimated at US$20.23 billion in 2015 Tourism is one of London's prime industries, employing the equivalent of 350,000 full-time workers in 2003, and the city accounts for 54% of all inbound visitor spend in UK. As of 2016 London is rated as the world top ranked city destination by TripAdvisor users.

Answer: Tourism


Question: What did NBC delay for the west coast primetime?, Context: CBC's sports coverage has also attained high viewership in border markets, including its coverage of the NHL's Stanley Cup Playoffs, which was generally considered to be more complete and consistent than coverage by other networks such as NBC. Its coverage of the Olympic Games also found a significant audience in border regions, primarily due to the fact that CBC aired more events live than NBC's coverage, which had been criticized in recent years for tape delaying events to air in primetime, even if the event is being held in a market in the Pacific Time Zone during primetime hours on the East (where it would still be delayed for West coast primetime).

Answer: Olympic Games


Question: what machine is mentioned first?, Context: Eventually, when it was more common for electric recordings to be played back electrically in the 1930s and 1940s, the overall tone was much like listening to a radio of the era. Magnetic pickups became more common and were better designed as time went on, making it possible to improve the damping of spurious resonances. Crystal pickups were also introduced as lower cost alternatives. The dynamic or moving coil microphone was introduced around 1930 and the velocity or ribbon microphone in 1932. Both of these high quality microphones became widespread in motion picture, radio, recording, and public address applications.

Answer:
radio