TASK DEFINITION: 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.
PROBLEM: Passage: Before the actual research explicitly devoted to the complexity of algorithmic problems started off, numerous foundations were laid out by various researchers. Most influential among these was the definition of Turing machines by Alan Turing in 1936, which turned out to be a very robust and flexible simplification of a computer.

SOLUTION: What were laid out by various companies?

PROBLEM: Passage: Noteworthy Irish mandolinists include Andy Irvine (who, like Johnny Moynihan, almost always tunes the top E down to D, to achieve an open tuning of GDAD), Paul Brady, Mick Moloney, Paul Kelly and Claudine Langille. John Sheahan and the late Barney McKenna, respectively fiddle player and tenor banjo player with The Dubliners, are also accomplished Irish mandolin players. The instruments used are either flat-backed, oval hole examples as described above (made by UK luthier Roger Bucknall of Fylde Guitars), or carved-top, oval hole instruments with arched back (made by Stefan Sobell in Northumberland). The Irish guitarist Rory Gallagher often played the mandolin on stage, and he most famously used it in the song "Going To My Hometown."

SOLUTION:  Who are some of the famous Italian Mandolinists?

PROBLEM: Passage: A number of technologies allow asphalt/bitumen to be mixed at much lower temperatures. These involve mixing with petroleum solvents to form "cutbacks" with reduced melting point, or mixtures with water to turn the asphalt/bitumen into an emulsion. Asphalt emulsions contain up to 70% asphalt/bitumen and typically less than 1.5% chemical additives. There are two main types of emulsions with different affinity for aggregates, cationic and anionic. Asphalt emulsions are used in a wide variety of applications. Chipseal involves spraying the road surface with asphalt emulsion followed by a layer of crushed rock, gravel or crushed slag. Slurry seal involves the creation of a mixture of asphalt emulsion and fine crushed aggregate that is spread on the surface of a road. Cold-mixed asphalt can also be made from asphalt emulsion to create pavements similar to hot-mixed asphalt, several inches in depth and asphalt emulsions are also blended into recycled hot-mix asphalt to create low-cost pavements.

SOLUTION:
What allows asphalt to be mixed at higher temperatures?