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 Input:
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 7–10% 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.

Ex Output:
What percentage of concrete is in mastic asphalt?


Ex Input:
Passage: The thalidomide tragedy resurrected Kefauver's bill to enhance drug regulation that had stalled in Congress, and the Kefauver-Harris Amendment became law on 10 October 1962. Manufacturers henceforth had to prove to FDA that their drugs were effective as well as safe before they could go on the US market. The FDA received authority to regulate advertising of prescription drugs and to establish good manufacturing practices. The law required that all drugs introduced between 1938 and 1962 had to be effective. An FDA - National Academy of Sciences collaborative study showed that nearly 40 percent of these products were not effective. A similarly comprehensive study of over-the-counter products began ten years later.

Ex Output:
When did the FDA Amendment become a law?


Ex Input:
Passage: What little there was, started with Charles de Wailly's crypt in the church of St Leu-St Gilles (1773–80), and Claude Nicolas Ledoux's Barriere des Bonshommes (1785–89). First-hand evidence of Greek architecture was of very little importance to the French, due to the influence of Marc-Antoine Laugier's doctrines that sought to discern the principles of the Greeks instead of their mere practices. It would take until Laboustre's Neo-Grec of the second Empire for the Greek revival to flower briefly in France.

Ex Output:

Who consider first-hand evidence of Greek architecture very important?