Question: In 2009 Tajikistan had 26 airports, 18 of which had paved runways, of which two had runways longer than 3,000 meters. The country's main airport is Dushanbe International Airport which as of April 2015, had regularly scheduled flights to major cities in Russia, Central Asia, as well as Delhi, Dubai, Frankfurt, Istanbul, Kabul, Tehran, and Urumqi amongst others. There are also international flights, mainly to Russia, from Khujand Airport in the northern part of the country as well as limited international services from Kulob Airport, and Qurghonteppa International Airport. Khorog Airport is a domestic airport and also the only airport in the sparsely populated eastern half of the country.
Is there an answer to this question: In 2019, Tajikistan had how many airports?

Answer: unanswerable

Question: On March 27, 1964, the massive Good Friday earthquake killed 133 people and destroyed several villages and portions of large coastal communities, mainly by the resultant tsunamis and landslides. It was the second-most-powerful earthquake in the recorded history of the world, with a moment magnitude of 9.2. It was over one thousand times more powerful than the 1989 San Francisco earthquake. The time of day (5:36 pm), time of year and location of the epicenter were all cited as factors in potentially sparing thousands of lives, particularly in Anchorage.
Is there an answer to this question: What major event happened in Alaska on March 27, 1946 killing 133 people?

Answer: unanswerable

Question: Many other databases have application software that accesses the database on behalf of end-users, without exposing the DBMS interface directly. Application programmers may use a wire protocol directly, or more likely through an application programming interface. Database designers and database administrators interact with the DBMS through dedicated interfaces to build and maintain the applications' databases, and thus need some more knowledge and understanding about how DBMSs operate and the DBMSs' external interfaces and tuning parameters.
Is there an answer to this question: What is a way for programmers to avoid DBMS?

Answer: unanswerable

Question: A cappella [a kapplla] (Italian for "in the manner of the chapel") music is specifically group or solo singing without instrumental accompaniment, or a piece intended to be performed in this way. It contrasts with cantata, which is accompanied singing. The term "a cappella" was originally intended to differentiate between Renaissance polyphony and Baroque concertato style. In the 19th century a renewed interest in Renaissance polyphony coupled with an ignorance of the fact that vocal parts were often doubled by instrumentalists led to the term coming to mean unaccompanied vocal music. The term is also used, albeit rarely, as a synonym for alla breve.
Is there an answer to this question: At what point did Renaissance polyphony become popular again?

Answer:
19th century