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Many birds show plumage patterns in ultraviolet that are invisible to the human eye; some birds whose sexes appear similar to the naked eye are distinguished by the presence of ultraviolet reflective patches on their feathers. Male blue tits have an ultraviolet reflective crown patch which is displayed in courtship by posturing and raising of their nape feathers. Ultraviolet light is also used in foraging—kestrels have been shown to search for prey by detecting the UV reflective urine trail marks left on the ground by rodents. The eyelids of a bird are not used in blinking. Instead the eye is lubricated by the nictitating membrane, a third eyelid that moves horizontally. The nictitating membrane also covers the eye and acts as a contact lens in many aquatic birds. The bird retina has a fan shaped blood supply system called the pecten. Most birds cannot move their eyes, although there are exceptions, such as the great cormorant. Birds with eyes on the sides of their heads have a wide visual field, while birds with eyes on the front of their heads, such as owls, have binocular vision and can estimate the depth of field. The avian ear lacks external pinnae but is covered by feathers, although in some birds, such as the Asio, Bubo and Otus owls, these feathers form tufts which resemble ears. The inner ear has a cochlea, but it is not spiral as in mammals.
What covers the eye and acts as a contact lens in many aquatic birds?
A: nictitating membrane

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New Mexico is commonly thought to have Spanish as an official language alongside English because of its wide usage and legal promotion of Spanish in the state; however, the state has no official language. New Mexico's laws are promulgated bilingually in Spanish and English. Although English is the state government's paper working language, government business is often conducted in Spanish, particularly at the local level. Spanish has been spoken in the New Mexico-Colorado border and the contemporary U.S.–Mexico border since the 16th century.[citation needed]
Does Colorado have an official language?
A: unanswerable

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Sometimes not only church interiors but façades were also decorated with mosaics in Italy like in the case of the St Mark's Basilica in Venice (mainly from the 17th–19th centuries, but the oldest one from 1270–75, "The burial of St Mark in the first basilica"), the Cathedral of Orvieto (golden Gothic mosaics from the 14th century, many times redone) and the Basilica di San Frediano in Lucca (huge, striking golden mosaic representing the Ascension of Christ with the apostles below, designed by Berlinghiero Berlinghieri in the 13th century). The Cathedral of Spoleto is also decorated on the upper façade with a huge mosaic portraying the Blessing Christ (signed by one Solsternus from 1207).
the Basilica di San Frediano in Lucca has a large golden mosaic facade depicting which figure?
A: Christ

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Since the existence of the earliest Jewish diaspora, many Jews have aspired to return to "Zion" and the "Land of Israel", though the amount of effort that should be spent towards such an aim was a matter of dispute. The hopes and yearnings of Jews living in exile are an important theme of the Jewish belief system. After the Jews were expelled from Spain in 1492, some communities settled in Palestine. During the 16th century, Jewish communities struck roots in the Four Holy Cities—Jerusalem, Tiberias, Hebron, and Safed—and in 1697, Rabbi Yehuda Hachasid led a group of 1,500 Jews to Jerusalem. In the second half of the 18th century, Eastern European opponents of Hasidism, known as the Perushim, settled in Palestine.
Many Jews have aspired to return to where?
A:
Zion