Problem: Guam:

An infestation of the coconut rhinoceros beetle (CRB), Oryctes rhinoceros, was detected on Guam on September 12, 2007. CRB is not known to occur in the United States except in American Samoa. Delimiting surveys performed September 13–25, 2007 indicated that the infestation was limited to Tumon Bay and Faifai Beach, an area of approximately 900 acres (3.6 km2). Guam Department of Agriculture (GDA) placed quarantine on all properties within the Tumon area on October 5 and later expanded the quarantine to about 2,500 acres (10 km2) on October 25; approximately 0.5 miles (800 m) radius in all directions from all known locations of CRB infestation. CRB is native to Southern Asia and distributed throughout Asia and the Western Pacific including Sri Lanka, Upolu, Samoa, American Samoa, Palau, New Britain, West Irian, New Ireland, Pak Island and Manus Island (New Guinea), Fiji, Cocos (Keeling) Islands, Mauritius, and Reunion.

How long is Reunion Island?
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A: unanswerable


Problem: Georgian architecture:

The styles that resulted fall within several categories. In the mainstream of Georgian style were both Palladian architecture— and its whimsical alternatives, Gothic and Chinoiserie, which were the English-speaking world's equivalent of European Rococo. From the mid-1760s a range of Neoclassical modes were fashionable, associated with the British architects Robert Adam, James Gibbs, Sir William Chambers, James Wyatt, George Dance the Younger, Henry Holland and Sir John Soane. John Nash was one of the most prolific architects of the late Georgian era known as The Regency style, he was responsible for designing large areas of London. Greek Revival architecture was added to the repertory, beginning around 1750, but increasing in popularity after 1800. Leading exponents were William Wilkins and Robert Smirke.

What style of the early Georgian era was John Nash known for?
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A: unanswerable


Problem: Electric motor:

The rotating armature consists of one or more coils of wire wound around a laminated, magnetically "soft" ferromagnetic core. Current from the brushes flows through the commutator and one winding of the armature, making it a temporary magnet (an electromagnet). The magnetic field produced by the armature interacts with a stationary magnetic field produced by either PMs or another winding a field coil, as part of the motor frame. The force between the two magnetic fields tends to rotate the motor shaft. The commutator switches power to the coils as the rotor turns, keeping the magnetic poles of the rotor from ever fully aligning with the magnetic poles of the stator field, so that the rotor never stops (like a compass needle does), but rather keeps rotating as long as power is applied.

What non-motor device demonstrates why a commutator is needed?
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A: compass


Problem: Time:

The hourglass uses the flow of sand to measure the flow of time. They were used in navigation. Ferdinand Magellan used 18 glasses on each ship for his circumnavigation of the globe (1522). Incense sticks and candles were, and are, commonly used to measure time in temples and churches across the globe. Waterclocks, and later, mechanical clocks, were used to mark the events of the abbeys and monasteries of the Middle Ages. Richard of Wallingford (1292–1336), abbot of St. Alban's abbey, famously built a mechanical clock as an astronomical orrery about 1330. Great advances in accurate time-keeping were made by Galileo Galilei and especially Christiaan Huygens with the invention of pendulum driven clocks along with the invention of the minute hand by Jost Burgi.

How many hourglasses did Galileo Galilei use on each ship during his famous voyage across the globe?
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A:
unanswerable