Problem: Oklahoma:

Oklahoma is the nation's third-largest producer of natural gas, fifth-largest producer of crude oil, and has the second-greatest number of active drilling rigs, and ranks fifth in crude oil reserves. While the state ranked eighth for installed wind energy capacity in 2011, it is at the bottom of states in usage of renewable energy, with 94 percent of its electricity being generated by non-renewable sources in 2009, including 25 percent from coal and 46 percent from natural gas. Oklahoma has no nuclear power. Ranking 13th for total energy consumption per capita in 2009, Oklahoma's energy costs were 8th lowest in the nation.

How much of Oklahoma's electricity comes from non-renewable sources?
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A: 94 percent

Problem: BBC Television returned on 7 June 1946 at 15:00. Jasmine Bligh, one of the original announcers, made the first announcement, saying, 'Good afternoon everybody. How are you? Do you remember me, Jasmine Bligh?'. The Mickey Mouse cartoon of 1939 was repeated twenty minutes later.[unreliable source?] Alexandra Palace was the home base of the channel until the early 1950s when the majority of production moved into the newly acquired Lime Grove Studios.[original research?]
On what date did BBC return to the air after World War II?
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Answer: 7 June 1946

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The IANA time zone database maps a name to the named location's historical and predicted clock shifts. This database is used by many computer software systems, including most Unix-like operating systems, Java, and the Oracle RDBMS; HP's "tztab" database is similar but incompatible. When temporal authorities change DST rules, zoneinfo updates are installed as part of ordinary system maintenance. In Unix-like systems the TZ environment variable specifies the location name, as in TZ=':America/New_York'. In many of those systems there is also a system-wide setting that is applied if the TZ environment variable isn't set: this setting is controlled by the contents of the /etc/localtime file, which is usually a symbolic link or hard link to one of the zoneinfo files. Internal time is stored in timezone-independent epoch time; the TZ is used by each of potentially many simultaneous users and processes to independently localize time display.
What's the name of the HP database that's similar to IANA but not compatible with it?
A: tztab

Context and question: The name Nigeria was taken from the Niger River running through the country. This name was allegedly coined in the late 19th century by British journalist Flora Shaw, she was inspired by the name of the river, in preference to terms such as "Central Sudan". The origin of the name ''Nigeria'' came from the name of the Niger River. The word ( Niger ) is an alteration of the Tuareg name egerew n-igerewen used by inhabitants along the middle reaches of the river around Timbuktu prior to 19th-century European colonialism. Egerew n-igerewen means River of the Rivers.
What is Nigeria named after?
Answer: the Niger River

Question: A cardinal who is not a bishop is still entitled to wear and use the episcopal vestments and other pontificalia (episcopal regalia: mitre, crozier, zucchetto, pectoral cross and ring). Even if not a bishop, any cardinal has both actual and honorary precedence over non-cardinal patriarchs, as well as the archbishops and bishops who are not cardinals, but he cannot perform the functions reserved solely to bishops, such as ordination. The prominent priests who since 1962 were not ordained bishops on their elevation to the cardinalate were over the age of 80 or near to it, and so no cardinal who was not a bishop has participated in recent papal conclaves.
Is there an answer to this question: What is a cardinal who is a bishop entitles to wear and use?

Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The halogen lamp reduces uneven evaporation of the filament and eliminates darkening of the envelope by filling the lamp with a halogen gas at low pressure, rather than an inert gas. The halogen cycle increases the lifetime of the bulb and prevents its darkening by redepositing tungsten from the inside of the bulb back onto the filament. The halogen lamp can operate its filament at a higher temperature than a standard gas filled lamp of similar power without loss of operating life. Such bulbs are much smaller than normal incandescent bulbs, and are widely used where intense illumination is needed in a limited space. Fiber-optic lamps for optical microscopy is one typical application.
What is the most common situation when a halogen bulb is used?
A:
where intense illumination is needed in a limited space