Problem: British Empire:

The Caribbean initially provided England's most important and lucrative colonies, but not before several attempts at colonisation failed. An attempt to establish a colony in Guiana in 1604 lasted only two years, and failed in its main objective to find gold deposits. Colonies in St Lucia (1605) and Grenada (1609) also rapidly folded, but settlements were successfully established in St. Kitts (1624), Barbados (1627) and Nevis (1628). The colonies soon adopted the system of sugar plantations successfully used by the Portuguese in Brazil, which depended on slave labour, andat firstDutch ships, to sell the slaves and buy the sugar. To ensure that the increasingly healthy profits of this trade remained in English hands, Parliament decreed in 1651 that only English ships would be able to ply their trade in English colonies. This led to hostilities with the United Dutch Provincesa series of Anglo-Dutch Warswhich would eventually strengthen England's position in the Americas at the expense of the Dutch. In 1655, England annexed the island of Jamaica from the Spanish, and in 1666 succeeded in colonising the Bahamas.

When did England colonize the Bahamas?
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A: 1666

Problem: On February 29, 2012, Microsoft released Windows 8 Consumer Preview, the beta version of Windows 8, build 8250. Alongside other changes, the build removed the Start button from the taskbar for the first time since its debut on Windows 95; according to Windows manager Chaitanya Sareen, the Start button was removed to reflect their view that on Windows 8, the desktop was an "app" itself, and not the primary interface of the operating system. Windows president Steven Sinofsky said more than 100,000 changes had been made since the developer version went public. The day after its release, Windows 8 Consumer Preview had been downloaded over one million times. Like the Developer Preview, the Consumer Preview expired on January 15, 2013.
When was the beta version of Windows 8 made available to the public?
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Answer: February 29, 2012

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The original city council line-up of 14 members (nine district-based and five at-large positions) was based on a U.S. Justice Department mandate which took effect in 1979. At-large council members represent the entire city. Under the city charter, once the population in the city limits exceeded 2.1 million residents, two additional districts were to be added. The city of Houston's official 2010 census count was 600 shy of the required number; however, as the city was expected to grow beyond 2.1 million shortly thereafter, the two additional districts were added for, and the positions filled during, the August 2011 elections.
What population figure needs to be passed to add at large council members?
A: 2.1 million

Context and question: Although Kammu had abandoned universal conscription in 792, he still waged major military offensives to subjugate the Emishi, possible descendants of the displaced Jomon, living in northern and eastern Japan. After making temporary gains in 794, in 797 Kammu appointed a new commander, Sakanoue no Tamuramaro, under the title Sei-i Taishogun (Barbarian-subduing generalissimo). By 801 the shogun had defeated the Emishi and had extended the imperial domains to the eastern end of Honshu. Imperial control over the provinces was tenuous at best, however. In the ninth and tenth centuries, much authority was lost to the great families, who disregarded the Chinese-style land and tax systems imposed by the government in Kyoto. Stability came to Japan, but, even though succession was ensured for the imperial family through heredity, power again concentrated in the hands of one noble family, the Fujiwara which also helped Japan develop more.
Who was Kammu descended from?
Answer: unanswerable

Question: London's bus network is one of the largest in the world, running 24 hours a day, with about 8,500 buses, more than 700 bus routes and around 19,500 bus stops. In 2013, the network had more than 2 billion commuter trips per annum, more than the Underground. Around 850 million is taken in revenue each year. London has the largest wheelchair accessible network in the world and, from the 3rd quarter of 2007, became more accessible to hearing and visually impaired passengers as audio-visual announcements were introduced. The distinctive red double-decker buses are an internationally recognised trademark of London transport along with black cabs and the Tube.
Is there an answer to this question: How many buses does the London public bus network operate?

Answer: more than 700

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Many newer control systems are using wireless mesh open standards (such as ZigBee), which provides benefits including easier installation (no need to run control wires) and interoperability with other standards-based building control systems (e.g. security).
What type of standard do newer control systems use?
A:
wireless mesh open standards