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?
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Q: Passage: Unlike the Baroque style that it replaced, which was mostly used for palaces and churches, and had little representation in the British colonies, simpler Georgian styles were widely used by the upper and middle classes. Perhaps the best remaining house is the pristine Hammond-Harwood House (1774) in Annapolis, Maryland, designed by the colonial architect William Buckland and modelled on the Villa Pisani at Montagnana, Italy as depicted in Andrea Palladio's I quattro libri dell'architettura ("Four Books of Architecture").

A: What style was widely represented in British colonies?
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Q: Passage: Another cause is the rate at which income is taxed coupled with the progressivity of the tax system. A progressive tax is a tax by which the tax rate increases as the taxable base amount increases. In a progressive tax system, the level of the top tax rate will often have a direct impact on the level of inequality within a society, either increasing it or decreasing it, provided that income does not change as a result of the change in tax regime. Additionally, steeper tax progressivity applied to social spending can result in a more equal distribution of income across the board. The difference between the Gini index for an income distribution before taxation and the Gini index after taxation is an indicator for the effects of such taxation.

A:
What is it called when the tax rate and base amount decrease simultaneously?
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