Problem: Neptune:

Meanwhile, Le Verrier by letter urged Berlin Observatory astronomer Johann Gottfried Galle to search with the observatory's refractor. Heinrich d'Arrest, a student at the observatory, suggested to Galle that they could compare a recently drawn chart of the sky in the region of Le Verrier's predicted location with the current sky to seek the displacement characteristic of a planet, as opposed to a fixed star. On the evening of 23 September 1846, the day Galle received the letter, he discovered Neptune within 1 of where Le Verrier had predicted it to be, about 12 from Adams' prediction. Challis later realised that he had observed the planet twice, on 4 and 12 August, but did not recognise it as a planet because he lacked an up-to-date star map and was distracted by his concurrent work on comet observations.

When was Le Verrier born?
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A: unanswerable

Problem: Canadian football:

The Grey Cup was established in 1909 after being donated by Albert Grey, 4th Earl Grey, The Governor General of Canada as the championship of teams under the CRU for the Rugby Football Championship of Canada. Initially an amateur competition, it eventually became dominated by professional teams in the 1940s and early 1950s. The Ontario Rugby Football Union, the last amateur organization to compete for the trophy, withdrew from competition in 1954. The move ushered in the modern era of Canadian professional football.

When did amateur teams dominate the Canadian football championship?
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A: unanswerable

Problem: Bird:

Feathers being critical to the survival of a bird, require maintenance. Apart from physical wear and tear, feathers face the onslaught of fungi, ectoparasitic feather mites and birdlice. The physical condition of feathers are maintained by preening often with the application of secretions from the preen gland. Birds also bathe in water or dust themselves. While some birds dip into shallow water, more aerial species may make aerial dips into water and arboreal species often make use of dew or rain that collect on leaves. Birds of arid regions make use of loose soil to dust-bathe. A behaviour termed as anting in which the bird encourages ants to run through their plumage is also thought to help them reduce the ectoparasite load in feathers. Many species will spread out their wings and expose them to direct sunlight and this too is thought to help in reducing fungal and ectoparasitic activity that may lead to feather damage.

What is it called when birds encourage ants to run through their plumage?
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A: anting

Problem: Jews:

Genetic studies on Jews show that most Jews worldwide bear a common genetic heritage which originates in the Middle East, and that they bear their strongest resemblance to the peoples of the Fertile Crescent. The genetic composition of different Jewish groups shows that Jews share a common genetic pool dating back 4,000 years, as a marker of their common ancestral origin. Despite their long-term separation and beside their shared genetic origin, Jews also maintained a common culture, tradition, and language.

Genetic studies show that Jews bear their strongest resemblance to the peoples of where?
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A:
Fertile Crescent