Problem: Aircraft carrier:

The development of flattop vessels produced the first large fleet ships. In 1918, HMS Argus became the world's first carrier capable of launching and recovering naval aircraft. As a result of the Washington Naval Treaty of 1922, which limited the construction of new heavy surface combat ships, most early aircraft carriers were conversions of ships that were laid down (or had served) as different ship types: cargo ships, cruisers, battlecruisers, or battleships. These conversions gave rise to the Lexington-class aircraft carriers (1927), Akagi and Courageous class. Specialist carrier evolution was well underway, with several navies ordering and building warships that were purposefully designed to function as aircraft carriers by the mid-1920s, resulting in the commissioning of ships such as Hosho (1922), HMS Hermes (1924), and Bearn (1927). During World War II, these ships would become known as fleet carriers.[citation needed]

What did the Washington Naval Treaty of 1922 limit?
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A: the construction of new heavy surface combat ships

Problem: A political party is typically led by a party leader (the most powerful member and spokesperson representing the party), a party secretary (who maintains the daily work and records of party meetings), party treasurer (who is responsible for membership dues) and party chair (who forms strategies for recruiting and retaining party members, and also chairs party meetings). Most of the above positions are also members of the party executive, the leading organization which sets policy for the entire party at the national level. The structure is far more decentralized in the United States because of the separation of powers, federalism and the multiplicity of economic interests and religious sects. Even state parties are decentralized as county and other local committees are largely independent of state central committees. The national party leader in the U.S. will be the president, if the party holds that office, or a prominent member of Congress in opposition (although a big-state governor may aspire to that role). Officially, each party has a chairman for its national committee who is a prominent spokesman, organizer and fund-raiser, but without the status of prominent elected office holders.
Who maintains the daily work and records of party meetings?
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Answer: party secretary

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
It is common to classify wood as either softwood or hardwood. The wood from conifers (e.g. pine) is called softwood, and the wood from dicotyledons (usually broad-leaved trees, e.g. oak) is called hardwood. These names are a bit misleading, as hardwoods are not necessarily hard, and softwoods are not necessarily soft. The well-known balsa (a hardwood) is actually softer than any commercial softwood. Conversely, some softwoods (e.g. yew) are harder than many hardwoods.
What's an example of a softwood that isn't "soft," and is actually harder than a lot of hardwoods?
A: yew

Context and question: A cover story in BusinessWeek magazine claims that economists mostly failed to predict the worst international economic crisis since the Great Depression of the 1930s. The Wharton School of the University of Pennsylvania's online business journal examines why economists failed to predict a major global financial crisis. Popular articles published in the mass media have led the general public to believe that the majority of economists have failed in their obligation to predict the financial crisis. For example, an article in the New York Times informs that economist Nouriel Roubini warned of such crisis as early as September 2006, and the article goes on to state that the profession of economics is bad at predicting recessions. According to The Guardian, Roubini was ridiculed for predicting a collapse of the housing market and worldwide recession, while The New York Times labelled him "Dr. Doom".
What was economist Roubini called by the New York Times for predicting a collapse of the housing market?
Answer: "Dr. Doom"

Question: In the 20th century, new types of glass such as laminated glass, reinforced glass and glass bricks have increased the use of glass as a building material and resulted in new applications of glass. Multi-storey buildings are frequently constructed with curtain walls made almost entirely of glass. Similarly, laminated glass has been widely applied to vehicles for windscreens. While glass containers have always been used for storage and are valued for their hygienic properties, glass has been utilized increasingly in industry. Optical glass for spectacles has been used since the late Middle Ages. The production of lenses has become increasingly proficient, aiding astronomers as well as having other application in medicine and science. Glass is also employed as the aperture cover in many solar energy systems.
Is there an answer to this question: What type of power systems use glass?

Answer: solar

Problem: Mosaic:

The craft has also been popular in early medieval Rus, inherited as part of the Byzantine tradition. Yaroslav, the Grand Prince of the Kievan Rus' built a large cathedral in his capital, Kiev. The model of the church was the Hagia Sophia in Constantinople, and it was also called Saint Sophia Cathedral. It was built mainly by Byzantine master craftsmen, sent by Constantine Monomachos, between 1037 and 1046. Naturally the more important surfaces in the interior were decorated with golden mosaics. In the dome we can see the traditional stern Pantokrator supported by angels. Between the 12 windows of the drum were apostles and the four evangelists on the pendentives. The apse is dominated by an orant Theotokos with a Deesis in three medallions above. Below is a Communion of the Apostles.

What was used as a model for the church Yaroslav commissioned?
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A:
the Hagia Sophia