This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.

Q: However a log-periodic dipole array consists of a number of dipole elements of different lengths in order to obtain a somewhat directional antenna having an extremely wide bandwidth: these are frequently used for television reception in fringe areas. The dipole antennas composing it are all considered "active elements" since they are all electrically connected together (and to the transmission line). On the other hand, a superficially similar dipole array, the Yagi-Uda Antenna (or simply "Yagi"), has only one dipole element with an electrical connection; the other so-called parasitic elements interact with the electromagnetic field in order to realize a fairly directional antenna but one which is limited to a rather narrow bandwidth. The Yagi antenna has similar looking parasitic dipole elements but which act differently due to their somewhat different lengths. There may be a number of so-called "directors" in front of the active element in the direction of propagation, and usually a single (but possibly more) "reflector" on the opposite side of the active element.

A: What type of antenna formation is made up of multiple dipole elements of varying lengths?
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Q: China's network security and information technology leadership team was established February 27, 2014. The leadership team is tasked with national security and long-term development and co-ordination of major issues related to network security and information technology. Economic, political, cultural, social and military fields as related to network security and information technology strategy, planning and major macroeconomic policy are being researched. The promotion of national network security and information technology law are constantly under study for enhanced national security capabilities.

A: When was Chine's network security and information technology leadership team established?
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Q: The language was first introduced in North America when Russian explorers voyaged into Alaska and claimed it for Russia during the 1700s. Although most colonists left after the United States bought the land in 1867, a handful stayed and preserved the Russian language in this region to this day, although only a few elderly speakers of this unique dialect are left. Sizable Russian-speaking communities also exist in North America, especially in large urban centers of the U.S. and Canada, such as New York City, Philadelphia, Boston, Los Angeles, Nashville, San Francisco, Seattle, Spokane, Toronto, Baltimore, Miami, Chicago, Denver and Cleveland. In a number of locations they issue their own newspapers, and live in ethnic enclaves (especially the generation of immigrants who started arriving in the early 1960s). Only about 25% of them are ethnic Russians, however. Before the dissolution of the Soviet Union, the overwhelming majority of Russophones in Brighton Beach, Brooklyn in New York City were Russian-speaking Jews. Afterward, the influx from the countries of the former Soviet Union changed the statistics somewhat, with ethnic Russians and Ukrainians immigrating along with some more Russian Jews and Central Asians. According to the United States Census, in 2007 Russian was the primary language spoken in the homes of over 850,000 individuals living in the United States.

A:
Where did Russian explorers first reach North America?
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