Problem: Royal Dutch Shell:

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.

How many centralised businesses does Shell have?
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A: unanswerable


Problem: The MC controls the conferencing while it is active on the signaling plane, which is simply where the system manages conferencing creation, endpoint signaling and in-conferencing controls. This component negotiates parameters with every endpoint in the network and controls conferencing resources. While the MC controls resources and signaling negotiations, the MP operates on the media plane and receives media from each endpoint. The MP generates output streams from each endpoint and redirects the information to other endpoints in the conference.
Where does the videoconferencing system manage conferencing creation?
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Answer: the signaling plane


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The country currency is the Samoan tālā, issued and regulated by the Central Bank of Samoa. The economy of Samoa has traditionally been dependent on agriculture and fishing at the local level. In modern times, development aid, private family remittances from overseas, and agricultural exports have become key factors in the nation's economy. Agriculture employs two-thirds of the labour force, and furnishes 90% of exports, featuring coconut cream, coconut oil, noni (juice of the nonu fruit, as it is known in Samoan), and copra.
How much of the country uses the Samoa tala?
A: unanswerable


Context and question: The United States Mint produces Proof Sets specifically for collectors and speculators. Silver Proofs tend to be the standard designs but with the dime, quarter, and half dollar containing 90% silver. Starting in 1983 and ending in 1997, the Mint also produced proof sets containing the year's commemorative coins alongside the regular coins. Another type of proof set is the Presidential Dollar Proof Set where four special $1 coins are minted each year featuring a president. Because of budget constraints and increasing stockpiles of these relatively unpopular coins, the production of new Presidential dollar coins for circulation was suspended on December 13, 2011, by U.S. Treasury Secretary Timothy F. Geithner. Future minting of such coins will be made solely for collectors.
Other than the Silver Proof set, what other type of Proof set exists?
Answer: Presidential Dollar Proof Set


Question: In January 2010, YouTube launched an experimental version of the site that used the built-in multimedia capabilities of web browsers supporting the HTML5 standard. This allowed videos to be viewed without requiring Adobe Flash Player or any other plug-in to be installed. The YouTube site had a page that allowed supported browsers to opt into the HTML5 trial. Only browsers that supported HTML5 Video using the H.264 or WebM formats could play the videos, and not all videos on the site were available.
Is there an answer to this question:  What was the main benefit from the switch to HTML4?

Answer: unanswerable


Problem: Airport:

An airport is an aerodrome with facilities for flights to take off and land. Airports often have facilities to store and maintain aircraft, and a control tower. An airport consists of a landing area, which comprises an aerially accessible open space including at least one operationally active surface such as a runway for a plane to take off or a helipad, and often includes adjacent utility buildings such as control towers, hangars  and terminals. Larger airports may have fixed base operator services, airport aprons, air traffic control centres, passenger facilities such as restaurants and lounges, and emergency services.

What is the definition of a helipad?
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A:
unanswerable