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: A global drop in sea level at the end of the Devonian reversed early in the Carboniferous; this created the widespread epicontinental seas and carbonate deposition of the Mississippian. There was also a drop in south polar temperatures; southern Gondwana was glaciated throughout the period, though it is uncertain if the ice sheets were a holdover from the Devonian or not. These conditions apparently had little effect in the deep tropics, where lush coal swamps flourished within 30 degrees of the northernmost glaciers. A mid-Carboniferous drop in sea-level precipitated a major marine extinction, one that hit crinoids and ammonites especially hard. This sea-level drop and the associated unconformity in North America separate the Mississippian Period from the Pennsylvanian period.

A: What dropped world wide at the begining of the Devonian?
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Q: Passage: Furthermore, in terms of job prospects, as of 2014 the average starting salary of an Imperial graduate was the highest of any UK university. In terms of specific course salaries, the Sunday Times ranked Computing graduates from Imperial as earning the second highest average starting salary in the UK after graduation, over all universities and courses. In 2012, the New York Times ranked Imperial College as one of the top 10 most-welcomed universities by the global job market. In May 2014, the university was voted highest in the UK for Job Prospects by students voting in the Whatuni Student Choice Awards Imperial is jointly ranked as the 3rd best university in the UK for the quality of graduates according to recruiters from the UK's major companies.

A: What collegege had the highest higher rate in 2014 among graduates?
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Q: Passage: Traditionally, Shell was a heavily decentralised business worldwide (especially in the downstream) with companies in over 100 countries, each of which operated with a high degree of independence. The upstream tended to be far more centralised with much of the technical and financial direction coming from the central offices in The Hague. Nevertheless, there were very large "exploration and production" companies in a few major oil and gas production centres such as the United Kingdom (Shell Expro, a Joint Venture with Exxon), Nigeria, Brunei, and Oman.

A:
How many centralised businesses does Shell have?
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