This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.

Q: Passage: The logical format of an audio CD (officially Compact Disc Digital Audio or CD-DA) is described in a document produced in 1980 by the format's joint creators, Sony and Philips. The document is known colloquially as the Red Book CD-DA after the colour of its cover. The format is a two-channel 16-bit PCM encoding at a 44.1 kHz sampling rate per channel. Four-channel sound was to be an allowable option within the Red Book format, but has never been implemented. Monaural audio has no existing standard on a Red Book CD; thus, mono source material is usually presented as two identical channels in a standard Red Book stereo track (i.e., mirrored mono); an MP3 CD, however, can have audio file formats with mono sound.

A: What was the sampling rate for the four-channel sound?
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Q: Passage: The noise-based speed is defined as the exposure that will lead to a given signal-to-noise ratio on individual pixels. Two ratios are used, the 40:1 ("excellent image quality") and the 10:1 ("acceptable image quality") ratio. These ratios have been subjectively determined based on a resolution of 70 pixels per cm (178 DPI) when viewed at 25 cm (9.8 inch) distance. The signal-to-noise ratio is defined as the standard deviation of a weighted average of the luminance and color of individual pixels. The noise-based speed is mostly determined by the properties of the sensor and somewhat affected by the noise in the electronic gain and AD converter.

A: Which ratio was subjectively determined?
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Q: Passage: Historical narratives of manga tend to focus either on its recent, post-WWII history, or on attempts to demonstrates deep roots in the past, such as to the Choju-jinbutsu-giga picture scroll of the 12th and 13th centuries, or the early 19th-century Hokusai Manga. The first historical overview of Japanese comics was Seiki Hosokibara's Nihon Manga-Shi[i] in 1924. Early post-war Japanese criticism was mostly of a left-wing political nature until the 1986 publication for Tomofusa Kure's Modern Manga: The Complete Picture,[j] which de-emphasized politics in favour of formal aspects, such as structure and a "grammar" of comics. The field of manga studies increased rapidly, with numerous books on the subject appearing in the 1990s. Formal theories of manga have focused on developing a "manga expression theory",[k] with emphasis on spatial relationships in the structure of images on the page, distinguishing the medium from film or literature, in which the flow of time is the basic organizing element. Comics studies courses have proliferated at Japanese universities, and Japan Society for Studies in Cartoon and Comics (ja)[l] was established in 2001 to promote comics scholarship. The publication of Frederik L. Schodt's Manga! Manga! The World of Japanese Comics in 1983 led to the spread of use of the word manga outside Japan to mean "Japanese comics" or "Japanese-style comics".

A:
Which historical overview did Seiki Hosokibara reject?
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