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.
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Question: Passage: Mastic asphalt is a type of asphalt which differs from dense graded asphalt (asphalt concrete) in that it has a higher asphalt/bitumen (binder) content, usually around 710% of the whole aggregate mix, as opposed to rolled asphalt concrete, which has only around 5% added asphalt/bitumen. This thermoplastic substance is widely used in the building industry for waterproofing flat roofs and tanking underground. Mastic asphalt is heated to a temperature of 210 C (410 F) and is spread in layers to form an impervious barrier about 20 millimeters (0.79 inches) thick.

Answer: What percentage of concrete is in mastic asphalt?

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: For Germany, because an autarkic economic approach or an alliance with Britain were impossible, closer relations with the Soviet Union to obtain raw materials became necessary, if not just for economic reasons alone. Moreover, an expected British blockade in the event of war would create massive shortages for Germany in a number of key raw materials. After the Munich agreement, the resulting increase in German military supply needs and Soviet demands for military machinery, talks between the two countries occurred from late 1938 to March 1939. The third Soviet Five Year Plan required new infusions of technology and industrial equipment.[clarification needed] German war planners had estimated serious shortfalls of raw materials if Germany entered a war without Soviet supply.

Answer:
During conflict, what wouldn't prevent transport of materials?