instruction:
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.
question:
Passage: While its fellow Canadian broadcasters converted most of their transmitters to digital by the Canadian digital television transition deadline of August 31, 2011, CBC converted only about half of the analogue transmitters in mandatory areas to digital (15 of 28 markets with CBC Television stations, and 14 of 28 markets with Television de Radio-Canada stations). Due to financial difficulties reported by the corporation, the corporation published digital transition plans for none of its analogue retransmitters in mandatory markets to be converted to digital by the deadline. Under this plan, communities that receive analogue signals by rebroadcast transmitters in mandatory markets would lose their over-the-air signals as of the deadline. Rebroadcast transmitters account for 23 of the 48 CBC and Radio-Canada transmitters in mandatory markets. Mandatory markets losing both CBC and Radio-Canada over-the-air signals include London, Ontario (metropolitan area population 457,000) and Saskatoon, Saskatchewan (metro area population 257,000). In both of those markets, the corporation's television transmitters are the only ones that were not planned to be converted to digital by the deadline.
answer:
The CBC petitioned to change what original deadline for converting transmission from digital to analog?

question:
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.
answer:
Which ratio was subjectively determined?

question:
Passage: A famous example of Arabic poetry and Persian poetry on romance (love) is Layla and Majnun, dating back to the Umayyad era in the 7th century. It is a tragic story of undying love much like the later Romeo and Juliet, which was itself said to have been inspired by a Latin version of Layla and Majnun to an extent. Ferdowsi's Shahnameh, the national epic of Iran, is a mythical and heroic retelling of Persian history. Amir Arsalan was also a popular mythical Persian story, which has influenced some modern works of fantasy fiction, such as The Heroic Legend of Arslan.
answer:
What ers dates to the 700's?