Problem: Samurai:

A samurai could take concubines but their backgrounds were checked by higher-ranked samurai. In many cases, taking a concubine was akin to a marriage. Kidnapping a concubine, although common in fiction, would have been shameful, if not criminal. If the concubine was a commoner, a messenger was sent with betrothal money or a note for exemption of tax to ask for her parents' acceptance. Even though the woman would not be a legal wife, a situation normally considered a demotion, many wealthy merchants believed that being the concubine of a samurai was superior to being the legal wife of a commoner. When a merchant's daughter married a samurai, her family's money erased the samurai's debts, and the samurai's social status improved the standing of the merchant family. If a samurai's commoner concubine gave birth to a son, the son could inherit his father's social status.

Who thought being a concubine was better than being a wife?
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A: many wealthy merchants


Problem: Sahara:

The rainfall inhibition and the dissipation of cloud cover are most accentuated over the eastern section of the Sahara rather than the western. The prevailing air mass lying above the Sahara is the continental tropical (cT) air mass which is hot and dry. Hot, dry air masses primarily form over the North-African desert from the heating of the vast continental land area, and it affects the whole desert during most of the year. Because of this extreme heating process, a thermal low is usually noticed near the surface, and is the strongest and the most developed during the summertime. The Sahara High represents the eastern continental extension of the Azores High, centered over the North Atlantic Ocean. The subsidence of the Sahara High nearly reaches the ground during the coolest part of the year while it limits to the upper troposphere during the hottest periods.

What type of high is strongest in the summer?
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A: unanswerable


Problem: Windows 8:

An upgrade to Windows 8 known as Windows 8.1 was officially announced by Microsoft on May 14, 2013. Following a presentation devoted to the upgrade at Build 2013, a public beta version of the upgrade was released on June 26, 2013. Windows 8.1 was released to OEM hardware partners on August 27, 2013, and released publicly as a free download through Windows Store on October 17, 2013. Volume license customers and subscribers to MSDN Plus and TechNet Plus were initially unable to obtain the RTM version upon its release; a spokesperson said the policy was changed to allow Microsoft to work with OEMs "to ensure a quality experience at general availability." However, after criticism, Microsoft reversed its decision and released the RTM build on MSDN and TechNet on September 9, 2013.

When did Microsoft release the alpha version of Windows 8.1?
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A: unanswerable


Problem: San Diego:

San Diego and its backcountry are subject to periodic wildfires. In October 2003, San Diego was the site of the Cedar Fire, which has been called the largest wildfire in California over the past century. The fire burned 280,000 acres (1,100 km2), killed 15 people, and destroyed more than 2,200 homes. In addition to damage caused by the fire, smoke resulted in a significant increase in emergency room visits due to asthma, respiratory problems, eye irritation, and smoke inhalation; the poor air quality caused San Diego County schools to close for a week. Wildfires four years later destroyed some areas, particularly within the communities of Rancho Bernardo, Rancho Santa Fe, and Ramona.

How many homes were destroyed in the Cedar Fire?
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A:
more than 2,200