Problem: Buddhism:

Zen Buddhism is divided into two main schools: Rinzai () and Soto (), the former greatly favouring the use in meditation on the koan (, a meditative riddle or puzzle) as a device for spiritual break-through, and the latter (while certainly employing koans) focusing more on shikantaza or "just sitting".[note 13]

Zen Buddhism is divided into how many main schools?
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A: two

Problem: In August 1836, two real estate entrepreneursAugustus Chapman Allen and John Kirby Allenfrom New York, purchased 6,642 acres (26.88 km2) of land along Buffalo Bayou with the intent of founding a city. The Allen brothers decided to name the city after Sam Houston, the popular general at the Battle of San Jacinto, who was elected President of Texas in September 1836. The great majority of slaves in Texas came with their owners from the older slave states. Sizable numbers, however, came through the domestic slave trade. New Orleans was the center of this trade in the Deep South, but there were slave dealers in Houston. Thousands of enslaved African-Americans lived near the city before the Civil War. Many of them near the city worked on sugar and cotton plantations, while most of those in the city limits had domestic and artisan jobs. In 1860 forty-nine percent of the city's population was enslaved. A few slaves, perhaps as many as 2,000 between 1835 and 1865, came through the illegal African trade. Post-war Texas grew rapidly as migrants poured into the cotton lands of the state. They also brought or purchased enslaved African Americans, whose numbers nearly tripled in the state from 1850 to 1860, from 58,000 to 182,566.
What was the reason the Allen brothers sold land in 1836?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In 1867, Prince Alfred, Duke of Edinburgh and second son of Queen Victoria, visited the islands. The main settlement, Edinburgh of the Seven Seas, was named in honour of his visit. Lewis Carroll's youngest brother, the Reverend Edwin Heron Dodgson, served as an Anglican missionary and schoolteacher in Tristan da Cunha in the 1880s.
When did Lewis Carroll Dodgson visit the islands?
A: unanswerable

Context and question: Eleven days after Orsini's assassination attempt in France, Victoria's eldest daughter married Prince Frederick William of Prussia in London. They had been betrothed since September 1855, when Princess Victoria was 14 years old; the marriage was delayed by the Queen and Prince Albert until the bride was 17. The Queen and Albert hoped that their daughter and son-in-law would be a liberalising influence in the enlarging Prussian state. Victoria felt "sick at heart" to see her daughter leave England for Germany; "It really makes me shudder", she wrote to Princess Victoria in one of her frequent letters, "when I look round to all your sweet, happy, unconscious sisters, and think I must give them up too one by one." Almost exactly a year later, Princess Victoria gave birth to the Queen's first grandchild, Wilhelm, who would become the last German Kaiser.
Where did Victoria's oldest daughter get married?
Answer: London

Question: Philadelphia has dedicated landmarks to its sister cities. Dedicated in June 1976, the Sister Cities Plaza, a site of 0.5 acres (2,000 m2) located at 18th and Benjamin Franklin Parkway, honors Philadelphia's relationships with Tel Aviv and Florence which were its first sister cities. Another landmark, the Torun Triangle, honoring the sister city relationship with Torun, Poland, was constructed in 1976, west of the United Way building at 18th Street and the Benjamin Franklin Parkway. In addition, the Triangle contains the Copernicus monument. Renovations were made to Sister Cities Park in mid-2011 and on May 10, 2012, SCP was reopened and currently features an interactive fountain honoring Philadelphia's ten sister and friendship cities, a cafe and visitor's center, children's play area, outdoor garden, and boat pond, as well as pavilion built to environmentally friendly standards.
Is there an answer to this question: How many sister cities does Philadelphia have?

Answer: ten

Standard 35mm photographic film used for cinema projection has a much higher image resolution than HDTV systems, and is exposed and projected at a rate of 24 frames per second (frame/s). To be shown on standard television, in PAL-system countries, cinema film is scanned at the TV rate of 25 frame/s, causing a speedup of 4.1 percent, which is generally considered acceptable. In NTSC-system countries, the TV scan rate of 30 frame/s would cause a perceptible speedup if the same were attempted, and the necessary correction is performed by a technique called 3:2 Pulldown: Over each successive pair of film frames, one is held for three video fields (1/20 of a second) and the next is held for two video fields (1/30 of a second), giving a total time for the two frames of 1/12 of a second and thus achieving the correct average film frame rate.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): To be shown on SDTV in PAL-system countries, at what rate is cinema film not scanned?
Ah, so..
unanswerable