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: The Gregorian calendar is a solar calendar. A regular Gregorian year consists of 365 days, but as in the Julian calendar, in a leap year, a leap day is added to February. In the Julian calendar a leap year occurs every 4 years, but the Gregorian calendar omits 3 leap days every 400 years. In the Julian calendar, this leap day was inserted by doubling 24 February, and the Gregorian reform did not change the date of the leap day. In the modern period, it has become customary to number the days from the beginning of the month, and February 29th is often considered as the leap day. Some churches, notably the Roman Catholic Church, delay February festivals after the 23rd by one day in leap years.
answer:
What calendar is a lunar calendar?


question:
Passage: All equipment must be suitable for a mixed-gender force. Combat helmets, rucksacks, combat boots, and flak jackets are designed to ensure women have the same level of protection and comfort as their male colleagues. The women's uniform is similar in design to the men's uniform, but conforms to the female figure, and is functional and practical. Women are also provided with an annual financial entitlement for the purchase of brassiere undergarments.
answer:
What is a requirement for equipment for the CE?


question:
Passage: Music was an important part of both secular and spiritual culture, and in the universities it made up part of the quadrivium of the liberal arts. From the early 13th century, the dominant sacred musical form had been the motet; a composition with text in several parts. From the 1330s and onwards, emerged the polyphonic style, which was a more complex fusion of independent voices. Polyphony had been common in the secular music of the Provençal troubadours. Many of these had fallen victim to the 13th-century Albigensian Crusade, but their influence reached the papal court at Avignon.
answer:

What was the dominant sacred musical form in the early 12th century?