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.

[Q]: Passage: Hyperbaric (high-pressure) medicine uses special oxygen chambers to increase the partial pressure of O
2 around the patient and, when needed, the medical staff. Carbon monoxide poisoning, gas gangrene, and decompression sickness (the 'bends') are sometimes treated using these devices. Increased O
2 concentration in the lungs helps to displace carbon monoxide from the heme group of hemoglobin. Oxygen gas is poisonous to the anaerobic bacteria that cause gas gangrene, so increasing its partial pressure helps kill them. Decompression sickness occurs in divers who decompress too quickly after a dive, resulting in bubbles of inert gas, mostly nitrogen and helium, forming in their blood. Increasing the pressure of O
2 as soon as possible is part of the treatment.
[A]: What medicines to do hyperbaric chambers use?

[Q]: Passage: When anti-German demonstrations erupted in Prague, Czechoslovakia, the Comintern ordered the Czech Communist Party to employ all of its strength to paralyze "chauvinist elements." Moscow soon forced the Communist Parties of France and Great Britain to adopt an anti-war position. On 7 September, Stalin called Georgi Dimitrov,[clarification needed] and the latter sketched a new Comintern line on the war. The new linewhich stated that the war was unjust and imperialistwas approved by the secretariat of the Communist International on 9 September. Thus, the various western Communist parties now had to oppose the war, and to vote against war credits. Although the French Communists had unanimously voted in Parliament for war credits on 2 September and on 19 September declared their "unshakeable will" to defend the country, on 27 September the Comintern formally instructed the party to condemn the war as imperialist. By 1 October the French Communists advocated listening to German peace proposals, and Communist leader Maurice Thorez deserted from the French Army on 4 October and fled to Russia. Other Communists also deserted from the army.
[A]: The eastern communists new rhetoric was that the war was?

[Q]: Passage: In 1986, Michael Dell brought in Lee Walker, a 51-year-old venture capitalist, as president and chief operating officer, to serve as Michael's mentor and implement Michael's ideas for growing the company. Walker was also instrumental in recruiting members to the board of directors when the company went public in 1988. Walker retired in 1990 due to health, and Michael Dell hired Morton Meyerson, former CEO and president of Electronic Data Systems to transform the company from a fast-growing medium-sized firm into a billion-dollar enterprise.
[A]:
What year didn't Michael Dell bring in Lee Walker to the company?