The problem: Answer a question about this article:
London's buildings are too diverse to be characterised by any particular architectural style, partly because of their varying ages. Many grand houses and public buildings, such as the National Gallery, are constructed from Portland stone. Some areas of the city, particularly those just west of the centre, are characterised by white stucco or whitewashed buildings. Few structures in central London pre-date the Great Fire of 1666, these being a few trace Roman remains, the Tower of London and a few scattered Tudor survivors in the City. Further out is, for example, the Tudor period Hampton Court Palace, England's oldest surviving Tudor palace, built by Cardinal Thomas Wolsey c.1515.
Of what material is London's National Gallery made?
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The answer: Portland stone

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The Greek shipping tradition recovered during Ottoman rule when a substantial merchant middle class developed, which played an important part in the Greek War of Independence. Today, Greek shipping continues to prosper to the extent that Greece has the largest merchant fleet in the world, while many more ships under Greek ownership fly flags of convenience. The most notable shipping magnate of the 20th century was Aristotle Onassis, others being Yiannis Latsis, George Livanos, and Stavros Niarchos.
Is the seafaring business still of any relevancy to the Greek economy ?
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The answer: Greek shipping continues to prosper to the extent that Greece has the largest merchant fleet in the world

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The Endangered Species Conservation Act (P. L. 91-135), passed in December, 1969, amended the original law to provide additional protection to species in danger of "worldwide extinction" by prohibiting their importation and subsequent sale in the United States. It expanded the Lacey Act's ban on interstate commerce to include mammals, reptiles, amphibians, mollusks and crustaceans. Reptiles were added mainly to reduce the rampant poaching of alligators and crocodiles. This law was the first time that invertebrates were included for protection.
How did the Endangered Species Conservation Act benefit endangered species?
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The answer: by prohibiting their importation and subsequent sale in the United States

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Since the end of the World Wars, the term "great power" has been joined by a number of other power classifications. Foremost among these is the concept of the superpower, used to describe those nations with overwhelming power and influence in the rest of the world. It was first coined in 1944 by William T.R. Fox and according to him, there were three superpowers: the British Empire, the United States, and the Soviet Union. But by the mid-1950s the British Empire lost its superpower status, leaving the United States and the Soviet Union as the world's superpowers.[nb 2] The term middle power has emerged for those nations which exercise a degree of global influence, but are insufficient to be decisive on international affairs. Regional powers are those whose influence is generally confined to their region of the world.
Who lost their superpower status in 1950s?
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The answer:
British Empire