This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.

Q: Passage: At the 1912 Salon d'Automne an architectural installation was exhibited that quickly became known as Maison Cubiste (Cubist House), signed Raymond Duchamp-Villon and Andre Mare along with a group of collaborators. Metzinger and Gleizes in Du "Cubisme", written during the assemblage of the "Maison Cubiste", wrote about the autonomous nature of art, stressing the point that decorative considerations should not govern the spirit of art. Decorative work, to them, was the "antithesis of the picture". "The true picture" wrote Metzinger and Gleizes, "bears its raison d'etre within itself. It can be moved from a church to a drawing-room, from a museum to a study. Essentially independent, necessarily complete, it need not immediately satisfy the mind: on the contrary, it should lead it, little by little, towards the fictitious depths in which the coordinative light resides. It does not harmonize with this or that ensemble; it harmonizes with things in general, with the universe: it is an organism...". "Mare's ensembles were accepted as frames for Cubist works because they allowed paintings and sculptures their independence", writes Christopher Green, "creating a play of contrasts, hence the involvement not only of Gleizes and Metzinger themselves, but of Marie Laurencin, the Duchamp brothers (Raymond Duchamp-Villon designed the facade) and Mare's old friends Leger and Roger La Fresnaye". La Maison Cubiste was a fully furnished house, with a staircase, wrought iron banisters, a living roomthe Salon Bourgeois, where paintings by Marcel Duchamp, Metzinger (Woman with a Fan), Gleizes, Laurencin and Leger were hungand a bedroom. It was an example of L'art decoratif, a home within which Cubist art could be displayed in the comfort and style of modern, bourgeois life. Spectators at the Salon d'Automne passed through the full-scale 10-by-3-meter plaster model of the ground floor of the facade, designed by Duchamp-Villon. This architectural installation was subsequently exhibited at the 1913 Armory Show, New York, Chicago and Boston, listed in the catalogue of the New York exhibit as Raymond Duchamp-Villon, number 609, and entitled "Facade architectural, plaster" (Facade architecturale).

A: What type of boat was La Maison Cubist?
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Q: Passage: To prevent the risk of out-of-phase supplies mixing, sections of line fed from different feeder stations must be kept strictly isolated. This is achieved by Neutral Sections (also known as Phase Breaks), usually provided at feeder stations and midway between them although, typically, only half are in use at any time, the others being provided to allow a feeder station to be shut down and power provided from adjacent feeder stations. Neutral Sections usually consist of an earthed section of wire which is separated from the live wires on either side by insulating material, typically ceramic beads, designed so that the pantograph will smoothly run from one section to the other. The earthed section prevents an arc being drawn from one live section to the other, as the voltage difference may be higher than the normal system voltage if the live sections are on different phases and the protective circuit breakers may not be able to safely interrupt the considerable current that would flow. To prevent the risk of an arc being drawn across from one section of wire to earth, when passing through the neutral section, the train must be coasting and the circuit breakers must be open. In many cases, this is done manually by the drivers. To help them, a warning board is provided just before both the neutral section and an advance warning some distance before. A further board is then provided after the neutral section to tell drivers to re-close the circuit breaker, although drivers must not do this until the rear pantograph has passed this board. In the UK, a system known as Automatic Power Control (APC) automatically opens and closes the circuit breaker, this being achieved by using sets of permanent magnets alongside the track communicating with a detector on the train. The only action needed by the driver is to shut off power and coast and therefore warning boards are still provided at and on the approach to neutral sections.

A: Charged Sections consist of an earthed section of what?
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Q: Passage: Uranium-238 is the most stable isotope of uranium, with a half-life of about 4.468109 years, roughly the age of the Earth. Uranium-235 has a half-life of about 7.13108 years, and uranium-234 has a half-life of about 2.48105 years. For natural uranium, about 49% of its alpha rays are emitted by each of 238U atom, and also 49% by 234U (since the latter is formed from the former) and about 2.0% of them by the 235U. When the Earth was young, probably about one-fifth of its uranium was uranium-235, but the percentage of 234U was probably much lower than this.

A:
What isotope of uranium has the least stability?
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