Part 1. Definition
In this task, you're given a question, along with a context passage which has extra information available on certain terms mentioned in it. Your job is to determine which sentence(s) from the passage can be used to search for further information needed to answer the question.
Part 2. Example
Question: When did the operation during which the 704th dropped supplies to allied troops near Nijmegen begin? Passage: The group was occasionally diverted from strategic missions to carry out air support and interdiction missions. It supported Operation Overlord, the invasion of Normandy by attacking transportation targets, including bridges, along with airfields and strong points in France. On D Day, the squadron and the rest of the 446th Group led the first heavy bomber mission of the day. The 446th aided ground forces at Caen and Saint-Lo during July by hitting bridges, gun batteries, and enemy troops. During Operation Market Garden, the attempt to seize a bridgehead across the Rhine in the Netherlands, the 704th dropped supplies to allied troops near Nijmegen. It struck lines of communications during the Battle of the Bulge. During Operation Varsity in March 1945, it supplied ground and airborne troops near Wesel. The squadron flew its last combat mission on 25 April 1945 against Salzburg, Austria. The group had flown 273 missions and had lost 58 aircraft during the war,
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Answer: During Operation Market Garden, the attempt to seize a bridgehead across the Rhine in the Netherlands, the 704th dropped supplies to allied troops near Nijmegen.
Explanation: The passage describes the 704th's actions during Operation Market Garden.
Part 3. Exercise
Question: How many years after the initial construction of the Great Northern Railway was Enfield Station built? Passage:The original Enfield Station in Windmill Hill opened on 1 April 1871 as the terminus for the Great Northern Railway branch line from Alexandra Palace. By 1887, 37 trains a day left Enfield, mainly for King's Cross, but also to Broad Street and until 1907, to Woolwich and Victoria. The station building was a two-storey twin-gabled house, similar in style to the single-storey building at Palmers Green. It was sited lengthways across the end of the track. The single island platform was covered by a wide canopy for much of its length. Enfield Station had been intended to bring prosperous middle-class commuters to the area. A journalist visiting the station in 1885, saw a sign advertising cheap workmen's tickets for trains scheduled to arrive in London before 8 am, only to find that the timetable showed that there were no trains that met that criterion. The old Enfield Station closed to passengers in 1910 and was replaced by the present station, but remained in use as a goods depot until 1974. The surviving buildings were demolished and replaced in the 2000s with housing along a new street, Gladbeck Way.

Answer:
The original Enfield Station in Windmill Hill opened on 1 April 1871 as the terminus for the Great Northern Railway branch line from Alexandra Palace