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.

[EX Q]: Passage: An alloy is a mixture of metals or a mixture of a metal and another element. Alloys are defined by metallic bonding character. An alloy may be a solid solution of metal elements (a single phase) or a mixture of metallic phases (two or more solutions). Intermetallic compounds are alloys with a defined stoichiometry and crystal structure. Zintl phases are also sometimes considered alloys depending on bond types (see also: Van Arkel-Ketelaar triangle for information on classifying bonding in binary compounds).
[EX A]: What is always a mixture of metal and other elements?

[EX Q]: Passage: The meaning of federalism, as a political movement, and of what constitutes a 'federalist', varies with country and historical context.[citation needed] Movements associated with the establishment or development of federations can exhibit either centralising or decentralising trends.[citation needed] For example, at the time those nations were being established, factions known as "federalists" in the United States and Australia advocated the formation of strong central government. Similarly, in European Union politics, federalists mostly seek greater EU integration. In contrast, in Spain and in post-war Germany, federal movements have sought decentralisation: the transfer of power from central authorities to local units. In Canada, where Quebec separatism has been a political force for several decades, the "federalist" impulse aims to keep Quebec inside Canada.
[EX A]: What isn't the meaning of federalism?

[EX Q]: Passage: This makes for a large number of takeoffs and landings and it is not unusual for flights to be delayed in the holding pattern before landing. Following the airport's master plan, Infraero built a second runway, which was finished in 2006. In 2007, the airport handled 11,119,872 passengers. The main building's third floor, with 12 thousand square meters, has a panoramic deck, a food court, shops, four movie theatres with total capacity of 500 people, and space for exhibitions. Brasília Airport has 136 vendor spaces. The airport is located about 11 km (6.8 mi) from the central area of Brasília, outside the metro system. The area outside the airport's main gate is lined with taxis as well as several bus line services which connect the airport to Brasília's central district. The parking lot accommodates 1,200 cars. The airport is serviced by domestic and regional airlines (TAM, GOL, Azul, WebJET, Trip and Avianca), in addition to a number of international carriers. In 2012, Brasília's International Airport was won by the InfrAmerica consortium, formed by the Brazilian engineering company ENGEVIX and the Argentine Corporacion America holding company, with a 50% stake each. During the 25-year concession, the airport may be expanded to up to 40 million passengers a year.
[EX A]:
What did Avianca build by following the airport master plan?