Problem: BeiDou Navigation Satellite System:

In December 2011, the system went into operation on a trial basis. It has started providing navigation, positioning and timing data to China and the neighbouring area for free from 27 December. During this trial run, Compass will offer positioning accuracy to within 25 meters, but the precision will improve as more satellites are launched. Upon the system's official launch, it pledged to offer general users positioning information accurate to the nearest 10 m, measure speeds within 0.2 m per second, and provide signals for clock synchronisation accurate to 0.02 microseconds.

During the trial period, within how many meters was the NSEW system's positioning accuracy?
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A: unanswerable


Problem: John Kerry:

Alexandra was born days before Kerry began law school. In 1982, Julia asked Kerry for a separation while she was suffering from severe depression. They were divorced on July 25, 1988, and the marriage was formally annulled in 1997. "After 14 years as a political wife, I associated politics only with anger, fear and loneliness" she wrote in A Change of Heart, her book about depression. Thorne later married Richard Charlesworth, an architect, and moved to Bozeman, Montana, where she became active in local environmental groups such as the Greater Yellowstone Coalition. Thorne supported Kerry's 2004 presidential run. She died of cancer on April 27, 2006.

When did Kerry and his wife divorce?
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A: July 25, 1988


Problem: Karl Popper:

Karl Popper was born in Vienna (then in Austria-Hungary) in 1902, to upper middle-class parents. All of Karl Popper's grandparents were Jewish, but the Popper family converted to Lutheranism before Karl was born, and so he received Lutheran baptism. They understood this as part of their cultural assimilation, not as an expression of devout belief. Karl's father Simon Siegmund Carl Popper was a lawyer from Bohemia and a doctor of law at the Vienna University, and mother Jenny Schiff was of Silesian and Hungarian descent. After establishing themselves in Vienna, the Poppers made a rapid social climb in Viennese society: Simon Siegmund Carl became a partner in the law firm of Vienna's liberal Burgomaster Herr Grübl and, after Grübl's death in 1898, Simon took over the business. (Malachi Hacohen records that Herr Grübl's first name was Raimund, after which Karl received his middle name. Popper himself, in his autobiography, erroneously recalls that Herr Grübl's first name was Carl.) His father was a bibliophile who had 12,000–14,000 volumes in his personal library. Popper inherited both the library and the disposition from him.

What was Karl Popper's mother's profession?
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A: unanswerable


Problem: Software testing:

There are generally four recognized levels of tests: unit testing, integration testing, component interface testing, and system testing. Tests are frequently grouped by where they are added in the software development process, or by the level of specificity of the test. The main levels during the development process as defined by the SWEBOK guide are unit-, integration-, and system testing that are distinguished by the test target without implying a specific process model. Other test levels are classified by the testing objective.

What is classified by the pretesting objective?
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A:
unanswerable