Problem: Poultry:

In many countries, national and regional poultry shows are held where enthusiasts exhibit their birds which are judged on certain phenotypical breed traits as specified by their respective breed standards. The idea of poultry exhibition may have originated after cockfighting was made illegal, as a way of maintaining a competitive element in poultry husbandry. Breed standards were drawn up for egg-laying, meat-type, and purely ornamental birds, aiming for uniformity. Sometimes, poultry shows are part of general livestock shows, and sometimes they are separate events such as the annual "National Championship Show" in the United Kingdom organised by the Poultry Club of Great Britain.

What are the unknown poultry tournaments?
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A: unanswerable

Problem: Cotton:

In Iran (Persia), the history of cotton dates back to the Achaemenid era (5th century BC); however, there are few sources about the planting of cotton in pre-Islamic Iran. The planting of cotton was common in Merv, Ray and Pars of Iran. In Persian poets' poems, especially Ferdowsi's Shahname, there are references to cotton ("panbe" in Persian). Marco Polo (13th century) refers to the major products of Persia, including cotton. John Chardin, a French traveler of the 17th century who visited the Safavid Persia, spoke approvingly of the vast cotton farms of Persia.

What 13th century explorer saw cotton in Persia?
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A: Marco Polo

Problem: Prime minister:

Canada's constitution, being a 'mixed' or hybrid constitution (a constitution that is partly formally codified and partly uncodified) originally did not make any reference whatsoever to a prime minister, with her or his specific duties and method of appointment instead dictated by "convention". In the Constitution Act, 1982, passing reference to a "Prime Minister of Canada" is added, though only regarding the composition of conferences of federal and provincial first ministers.

What document in Canada has allowed for a prime minister since it was drafted?
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A: unanswerable

Problem: Chinese characters:

New characters can in principle be coined at any time, just as new words can be, but they may not be adopted. Significant historically recent coinages date to scientific terms of the 19th century. Specifically, Chinese coined new characters for chemical elements see chemical elements in East Asian languages which continue to be used and taught in schools in China and Taiwan. In Japan, in the Meiji era (specifically, late 19th century), new characters were coined for some (but not all) SI units, such as ( "meter" + "thousand, kilo-") for kilometer. These kokuji (Japanese-coinages) have found use in China as well see Chinese characters for SI units for details.

What can be coined at any time?
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A:
New characters