Problem: New York City:

New York has architecturally noteworthy buildings in a wide range of styles and from distinct time periods, from the saltbox style Pieter Claesen Wyckoff House in Brooklyn, the oldest section of which dates to 1656, to the modern One World Trade Center, the skyscraper at Ground Zero in Lower Manhattan and currently the most expensive new office tower in the world.

The most expensive office tower built in the world today is what?
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A: One World Trade Center

Problem: Middle Ages:

In the 12th and 13th centuries, Europe produced economic growth and innovations in methods of production. Major technological advances included the invention of the windmill, the first mechanical clocks, the manufacture of distilled spirits, and the use of the astrolabe. Concave spectacles were invented around 1286 by an unknown Italian artisan, probably working in or near Pisa.

Near what city were concave spectacles invented?
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A: Pisa

Problem: Comprehensive school:

In 1976 the future Labour prime minister James Callaghan launched what became known as the 'great debate' on the education system. He went on to list the areas he felt needed closest scrutiny: the case for a core curriculum, the validity and use of informal teaching methods, the role of school inspection and the future of the examination system. Comprehensive school remains the most common type of state secondary school in England, and the only type in Wales. They account for around 90% of pupils, or 64% if one does not count schools with low-level selection. This figure varies by region.

What is the only kind of school not operating in Wales?
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A: unanswerable

Problem: Saint Helena:

The ship RMS Saint Helena runs between St Helena and Cape Town on a 5-day voyage, also visiting Ascension Island and Walvis Bay, and occasionally voyaging north to Tenerife and Portland, UK. It berths in James Bay, St Helena approximately thirty times per year. The RMS Saint Helena was due for decommissioning in 2010. However, its service life has been extended indefinitely until the airport is completed.

What needs to be completed before the RMS Saint Helena can be decommissioned?
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A:
the airport