Problem: Gothic architecture:

In France, simultaneously, the towering figure of the Gothic Revival was Eugene Viollet-le-Duc, who outdid historical Gothic constructions to create a Gothic as it ought to have been, notably at the fortified city of Carcassonne in the south of France and in some richly fortified keeps for industrial magnates. Viollet-le-Duc compiled and coordinated an Encyclopedie medievale that was a rich repertory his contemporaries mined for architectural details. He effected vigorous restoration of crumbling detail of French cathedrals, including the Abbey of Saint-Denis and famously at Notre Dame de Paris, where many of whose most "Gothic" gargoyles are Viollet-le-Duc's. He taught a generation of reform-Gothic designers and showed how to apply Gothic style to modern structural materials, especially cast iron.

What other famous American cathedral did Viollet-le-Duc work on?
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A: unanswerable

Problem: Drinking water supply and sanitation in Egypt is characterised by both achievements and challenges. Among the achievements are an increase of piped water supply between 1990 and 2010 from 89% to 100% in urban areas and from 39% to 93% in rural areas despite rapid population growth, the elimination of open defecation in rural areas during the same period, and in general a relatively high level of investment in infrastructure. Access to an improved water source in Egypt is now practically universal with a rate of 99%. About one half of the population is connected to sanitary sewers.
From 1990 to 2010 what was improvement in piped water supply to rural areas?
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Answer: 39% to 93%

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In 1950, Hayek left the London School of Economics for the University of Chicago, where he became a professor in the Committee on Social Thought. Hayek's salary was funded not by the university, but by an outside foundation. University of Chicago President Robert Hutchins was in the midst of a war with the U. of Chicago faculty over departmental autonomy and control, and Hayek got caught in the middle of that battle. Hutchins had been attempting to force all departments to adopt the neo-Thomist Great Books program of Mortimer Adler, and the U. of Chicago economists were sick of Hutchins' meddling. As the result the Economics department rejected Hutchins' pressure to hire Hayek, and Hayek became a part of the new Committee on Social Thought.
What did Hayek serve on after his initial rejection?
A: Committee on Social Thought

Context and question: The Qing dynasty (16441911) was founded after the fall of the Ming, the last Han Chinese dynasty, by the Manchus. The Manchus were formerly known as the Jurchens. When Beijing was captured by Li Zicheng's peasant rebels in 1644, the Chongzhen Emperor, the last Ming emperor, committed suicide. The Manchus then allied with former Ming general Wu Sangui and seized control of Beijing, which became the new capital of the Qing dynasty. The Mancus adopted the Confucian norms of traditional Chinese government in their rule of China proper. Schoppa, the editor of The Columbia Guide to Modern Chinese History argues, "A date around 1780 as the beginning of modern China is thus closer to what we know today as historical 'reality'. It also allows us to have a better baseline to understand the precipitous decline of the Chinese polity in the nineteenth and twentieth centuries."
The Qing dynasty formed after what event?
Answer: after the fall of the Ming

Question: Windows 8 introduces a new style of application, Windows Store apps. According to Microsoft developer Jensen Harris, these apps are to be optimized for touchscreen environments and are more specialized than current desktop applications. Apps can run either in a full-screen mode, or be snapped to the side of a screen. Apps can provide toast notifications on screen or animate their tiles on the Start screen with dynamic content. Apps can use "contracts"; a collection of hooks to provide common functionality that can integrate with other apps, including search and sharing. Apps can also provide integration with other services; for example, the People app can connect to a variety of different social networks and services (such as Facebook, Skype, and People service), while the Photos app can aggregate photos from services such as Facebook and Flickr.
Is there an answer to this question: What aren't contracts?

Answer: unanswerable

Problem: Airport:

At all airports the use of a traffic pattern (often called a traffic circuit outside the U.S.) is possible. They may help to assure smooth traffic flow between departing and arriving aircraft. There is no technical need within modern aviation for performing this pattern, provided there is no queue. And due to the so-called SLOT-times, the overall traffic planning tend to assure landing queues are avoided. If for instance an aircraft approaches runway 17 (which has a heading of approx. 170 degrees) from the north (coming from 360/0 degrees heading towards 180 degrees), the aircraft will land as fast as possible by just turning 10 degrees and follow the glidepath, without orbit the runway for visual reasons, whenever this is possible. For smaller piston engined airplanes at smaller airfields without ILS equipment, things are very differently though.

What is it like for aircraft landing at small airfields as fast as possible while following the glidepath?
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A:
unanswerable