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: A new generation of clubs such as Liverpool's Cream and the Ministry of Sound were opened to provide a venue for more commercial sounds. Major record companies began to open "superclubs" promoting their own acts. These superclubs entered into sponsorship deals initially with fast food, soft drinks, and clothing companies. Flyers in clubs in Ibiza often sported many corporate logos. A new subgenre, Chicago hard house, was developed by DJs such as Bad Boy Bill, DJ Lynnwood, DJ Irene, Richard "Humpty" Vission and DJ Enrie, mixing elements of Chicago house, funky house and hard house together. Additionally, Producers such as George Centeno, Darren Ramirez, and Martin O. Cairo would develop the Los Angeles Hard House sound. Similar to gabber or hardcore techno from the Netherlands, this sound was often associated with the "rebel" culture of the time. These 3 producers are often considered "ahead of their time" since many of the sounds they engineered during the late 20th century became more prominent during the 21st century.

SOLUTION: Where was a new type of club called Darren Located?

PROBLEM: Passage: There has, however, been interest among railroad operators in returning to DC use at higher voltages than previously used. At the same voltage, DC often has less loss than AC, and for this reason high-voltage direct current is already used on some bulk power transmission lines. DC avoids the electromagnetic radiation inherent with AC, and on a railway this also reduces interference with signalling and communications and mitigates hypothetical EMF risks. DC also avoids the power factor problems of AC. Of particular interest to railroading is that DC can supply constant power with a single ungrounded wire. Constant power with AC requires three-phase transmission with at least two ungrounded wires. Another important consideration is that mains-frequency 3-phase AC must be carefully planned to avoid unbalanced phase loads. Parts of the system are supplied from different phases on the assumption that the total loads of the 3 phases will even out. At the phase break points between regions supplied from different phases, long insulated supply breaks are required to avoid them being shorted by rolling stock using more than one pantograph at a time. A few railroads have tried 3-phase but its substantial complexity has made single-phase standard practice despite the interruption in power flow that occurs twice every cycle. An experimental 6 kV DC railway was built in the Soviet Union.

SOLUTION: Railroad operators have shown little interest in returning to what?

PROBLEM: Passage: Warsaw was occupied by Germany from 4 August 1915 until November 1918. The Allied Armistice terms required in Article 12 that Germany withdraw from areas controlled by Russia in 1914, which included Warsaw. Germany did so, and underground leader Piłsudski returned to Warsaw on 11 November and set up what became the Second Polish Republic, with Warsaw the capital. In the course of the Polish-Bolshevik War of 1920, the huge Battle of Warsaw was fought on the eastern outskirts of the city in which the capital was successfully defended and the Red Army defeated. Poland stopped by itself the full brunt of the Red Army and defeated an idea of the "export of the revolution".

SOLUTION:
How long was Germany occupied by Poland?