Problem: Compact disc:

The CD was planned to be the successor of the gramophone record for playing music, rather than primarily as a data storage medium. From its origins as a musical format, CDs have grown to encompass other applications. In 1983, following the CD's introduction, Immink and Braat presented the first experiments with erasable compact discs during the 73rd AES Convention. In June 1985, the computer-readable CD-ROM (read-only memory) and, in 1990, CD-Recordable were introduced, also developed by both Sony and Philips. Recordable CDs were a new alternative to tape for recording music and copying music albums without defects introduced in compression used in other digital recording methods. Other newer video formats such as DVD and Blu-ray use the same physical geometry as CD, and most DVD and Blu-ray players are backward compatible with audio CD.

When was the DVD first released?
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A: unanswerable


Problem: Web browser:

A browser extension is a computer program that extends the functionality of a web browser. Every major web browser supports the development of browser extensions.

What does every computer program support?
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A: unanswerable


Problem: Sexual orientation:

Scientists do not know the exact cause of sexual orientation, but they believe that it is caused by a complex interplay of genetic, hormonal, and environmental influences. They favor biologically-based theories, which point to genetic factors, the early uterine environment, both, or the inclusion of genetic and social factors. There is no substantive evidence which suggests parenting or early childhood experiences play a role when it comes to sexual orientation. Research over several decades has demonstrated that sexual orientation ranges along a continuum, from exclusive attraction to the opposite sex to exclusive attraction to the same sex.

What can scientifically be considered the main factors in somebodys sexual orientation?
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A: they believe that it is caused by a complex interplay of genetic, hormonal, and environmental influences.


Problem: Valencia:

The inevitable march to civil war and the combat in Madrid resulted in the removal of the capital of the Republic to Valencia. On 6 November 1936 the city became the capital of Republican Spain under the control of the prime minister Manuel Azana; the government moved to the Palau de Benicarló, its ministries occupying various other buildings. The city was heavily bombarded by air and sea, necessitating the construction of over two hundred bomb shelters to protect the population. On 13 January 1937 the city was first shelled by a vessel of the Fascist Italian Navy, which was blockading the port by the order of Benito Mussolini. The bombardment intensified and inflicted massive destruction on several occasions; by the end of the war the city had survived 442 bombardments, leaving 2,831 dead and 847 wounded, although it is estimated that the death toll was higher, as the data given are those recognised by Francisco Franco's government. The Republican government passed to Juan Negrín on 17 May 1937 and on 31 October of that year moved to Barcelona. On 30 March 1939 Valencia surrendered and the Nationalist troops entered the city. The postwar years were a time of hardship for Valencians. During Franco's regime speaking or teaching Valencian was prohibited; in a significant reversal it is now compulsory for every schoolchild in Valencia.

How many bomb shelters were built?
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A:
over two hundred