Here is a question about this article: The mandolin's popularity in the United States was spurred by the success of a group of touring young European musicians known as the Estudiantina Figaro, or in the United States, simply the "Spanish Students." The group landed in the U.S. on January 2, 1880 in New York City, and played in Boston and New York to wildly enthusiastic crowds. Ironically, this ensemble did not play mandolins but rather bandurrias, which are also small, double-strung instruments that resemble the mandolin. The success of the Figaro Spanish Students spawned other groups who imitated their musical style and costumes. An Italian musician, Carlo Curti, hastily started a musical ensemble after seeing the Figaro Spanish Students perform; his group of Italian born Americans called themselves the "Original Spanish Students," counting on the American public to not know the difference between the Spanish bandurrias and Italian mandolins. The imitators' use of mandolins helped to generate enormous public interest in an instrument previously relatively unknown in the United States.
What is the answer to this question: When did the Estudiantina Figaro come to the US?
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So... January 2, 1880

Here is a question about this article: Among the first to study Russian dialects was Lomonosov in the 18th century. In the 19th, Vladimir Dal compiled the first dictionary that included dialectal vocabulary. Detailed mapping of Russian dialects began at the turn of the 20th century. In modern times, the monumental Dialectological Atlas of the Russian Language ( [dlktlitskj atls ruskv jzka]), was published in three folio volumes 19861989, after four decades of preparatory work.
What is the answer to this question: When were detailed maps of Russian dialects created?
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So... turn of the 20th century

Here is a question about this article: By the mid-7th century, English and Irish missionaries set out to convert the Frisians. The pope appointed their leader, Willibrordus, bishop of the Frisians. The tenure of Willibrordus is generally considered to be the beginning of the Bishopric of Utrecht. In 723, the Frankish leader Charles Martel bestowed the fortress in Utrecht and the surrounding lands as the base of the bishops. From then on Utrecht became one of the most influential seats of power for the Roman Catholic Church in the Netherlands. The archbishops of Utrecht were based at the uneasy northern border of the Carolingian Empire. In addition, the city of Utrecht had competition from the nearby trading centre Dorestad. After the fall of Dorestad around 850, Utrecht became one of the most important cities in the Netherlands. The importance of Utrecht as a centre of Christianity is illustrated by the election of the Utrecht-born Adriaan Florenszoon Boeyens as pope in 1522 (the last non-Italian pope before John Paul II).
What is the answer to this question: Who did the pope appoint Bishop
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So...
The pope appointed their leader, Willibrordus, bishop of the Frisians