Input: New Haven, Connecticut
New Haven has a long tradition of urban planning and a purposeful design for the city's layout. The city could be argued to have some of the first preconceived layouts in the country. Upon founding, New Haven was laid out in a grid plan of nine square blocks; the central square was left open, in the tradition of many New England towns, as the city green (a commons area). The city also instituted the first public tree planting program in America. As in other cities, many of the elms that gave New Haven the nickname "Elm City" perished in the mid-20th century due to Dutch Elm disease, although many have since been replanted. The New Haven Green is currently home to three separate historic churches which speak to the original theocratic nature of the city. The Green remains the social center of the city today. It was named a National Historic Landmark in 1970.

What was the cause of the sudden extinction of many of the elms in New Haven?
Output: Dutch Elm disease

Input: The Blitz
These decisions, apparently taken at the Luftflotte or Fliegerkorps level (see Organisation of the Luftwaffe (19331945)), meant attacks on individual targets were gradually replaced by what was, for all intents and purposes, an unrestricted area attack or Terrorangriff (Terror Attack). Part of the reason for this was inaccuracy of navigation. The effectiveness of British countermeasures against Knickebein, which was designed to avoid area attacks, forced the Luftwaffe to resort to these methods. The shift from precision bombing to area attack is indicated in the tactical methods and weapons dropped. KGr 100 increased its use of incendiaries from 1328 percent. By December, this had increased to 92 percent. Use of incendiaries, which were inherently inaccurate, indicated much less care was taken to avoid civilian property close to industrial sites. Other units ceased using parachute flares and opted for explosive target markers. Captured German air crews also indicated the homes of industrial workers were deliberately targeted.

What percentage of incendiaries were used in December?
Output: 92 percent

Input: Kievan Rus%27
It is not clearly documented when the title of the Grand Duke was first introduced, but the importance of the Kiev principality was recognized after the death of Sviatoslav I in 972 and the ensuing struggle between Vladimir the Great and Yaropolk I. The region of Kiev dominated the state of Kievan Rus' for the next two centuries. The Grand Prince ("velikiy kniaz'") of Kiev controlled the lands around the city, and his formally subordinate relatives ruled the other cities and paid him tribute. The zenith of the state's power came during the reigns of Vladimir the Great (9801015) and Prince Yaroslav I the Wise (10191054). Both rulers continued the steady expansion of Kievan Rus' that had begun under Oleg.

What years did Vladimir the Great reign as leader?
Output: 9801015

Input: Seven Years%27 War
On the eastern front, progress was very slow. The Russian army was heavily dependent upon its main magazines in Poland, and the Prussian army launched several successful raids against them. One of them, led by general Platen in September resulted in the loss of 2,000 Russians, mostly captured, and the destruction of 5,000 wagons. Deprived of men, the Prussians had to resort to this new sort of warfare, raiding, to delay the advance of their enemies. Nonetheless, at the end of the year, they suffered two critical setbacks. The Russians under Zakhar Chernyshev and Pyotr Rumyantsev stormed Kolberg in Pomerania, while the Austrians captured Schweidnitz. The loss of Kolberg cost Prussia its last port on the Baltic Sea. In Britain, it was speculated that a total Prussian collapse was now imminent.

What was the concern about Prussia in Britain?
Output:
. In Britain, it was speculated that a total Prussian collapse was now imminent.