Problem: Antenna (radio):

The radio signal's electrical component induces a voltage in the conductor. This causes an electrical current to begin flowing in the direction of the signal's instantaneous field. When the resulting current reaches the end of the conductor, it reflects, which is equivalent to a 180 degree change in phase. If the conductor is 14 of a wavelength long, current from the feed point will undergo 90 degree phase change by the time it reaches the end of the conductor, reflect through 180 degrees, and then another 90 degrees as it travels back. That means it has undergone a total 360 degree phase change, returning it to the original signal. The current in the element thus adds to the current being created from the source at that instant. This process creates a standing wave in the conductor, with the maximum current at the feed.

What part of the radio signal creates voltage?
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A: electrical component

Problem: Military history of the United States:

The Berbers along the Barbary Coast (modern day Libya) sent pirates to capture merchant ships and hold the crews for ransom. The U.S. paid protection money until 1801, when President Thomas Jefferson refused to pay and sent in the Navy to challenge the Barbary States, the First Barbary War followed. After the U.S.S. Philadelphia was captured in 1803, Lieutenant Stephen Decatur led a raid which successfully burned the captured ship, preventing Tripoli from using or selling it. In 1805, after William Eaton captured the city of Derna, Tripoli agreed to a peace treaty. The other Barbary states continued to raid U.S. shipping, until the Second Barbary War in 1815 ended the practice.

What city did William Eaton befriend to end the first Barbary War?
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A: unanswerable

Problem: Ottoman Empire:

As the Ottoman Empire gradually shrank in size, some 79 million Turkish-Muslims from its former territories in the Caucasus, Crimea, Balkans, and the Mediterranean islands migrated to Anatolia and Eastern Thrace. After the Empire lost the Balkan Wars (191213), it lost all its Balkan territories except East Thrace (European Turkey). This resulted in around 400,000 Muslims fleeing with the retreating Ottoman armies (with many dying from cholera brought by the soldiers), and with some 400,000 non-Muslims fleeing territory still under Ottoman rule. Justin McCarthy estimates that during the period 1821 to 1922 several million Muslims died in the Balkans, with the expulsion of a similar number.

When did the Balkan Wars take place?
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A: 191213

Problem: Greece:

The Greek national basketball team has a decades-long tradition of excellence in the sport, being considered among the world's top basketball powers. As of 2012, it ranked 4th in the world and 2nd in Europe. They have won the European Championship twice in 1987 and 2005, and have reached the final four in two of the last four FIBA World Championships, taking the second place in the world in 2006 FIBA World Championship, after a spectacular 10195 win against Team USA in the tournament's semifinal. The domestic top basketball league, A1 Ethniki, is composed of fourteen teams. The most successful Greek teams are Olympiacos, Panathinaikos, Aris Thessaloniki, AEK Athens and P.A.O.K. Greek basketball teams are the most successful in European basketball the last 25 years, having won as many as 9 Euroleagues since the establishment of the modern era Euroleague Final Four format in 1988, while no other nation has won more than 4 Euroleague championships in this period. Besides the 9 Euroleagues, Greek basketball teams (Panathinaikos, Olympiacos, Aris Thessaloniki, AEK Athens, P.A.O.K, Maroussi) have won 3 Triple Crowns, 5 Saporta Cups, 2 Korac Cups and 1 FIBA Europe Champions Cup. After the 2005 European Championship triumph of the Greek national basketball team, Greece became the reigning European Champion in both football and basketball.

The Greek national basketball team held what world ranking in 2012?
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A:
4th