Problem: Modern history:

Northern leaders agreed that victory would require more than the end of fighting. Secession and Confederate nationalism had to be totally repudiated and all forms of slavery or quasi-slavery had to be eliminated. Lincoln proved effective in mobilizing support for the war goals, raising large armies and supplying them, avoiding foreign interference, and making the end of slavery a war goal. The Confederacy had a larger area than it could defend, and it failed to keep its ports open and its rivers clear. The North kept up the pressure as the South could barely feed and clothe its soldiers. Its soldiers, especially those in the East under the command of General Robert E. Lee proved highly resourceful until they finally were overwhelmed by Generals Ulysses S. Grant and William T. Sherman in 1864–65, The Reconstruction Era (1863–77) began with the Emancipation proclamation in 1863, and included freedom, full citizenship and the vote for the Southern blacks. It was followed by a reaction that left the blacks in a second class status legally, politically, socially and economically until the 1960s.

Why couldn't the confederacy defend their ports?
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A: The Confederacy had a larger area than it could defend


Problem: Copyright infringement:

Title I of the U.S. DMCA, the WIPO Copyright and Performances and Phonograms Treaties Implementation Act has provisions that prevent persons from "circumvent[ing] a technological measure that effectively controls access to a work". Thus if a distributor of copyrighted works has some kind of software, dongle or password access device installed in instances of the work, any attempt to bypass such a copy protection scheme may be actionable – though the US Copyright Office is currently reviewing anticircumvention rulemaking under DMCA – anticircumvention exemptions that have been in place under the DMCA include those in software designed to filter websites that are generally seen to be inefficient (child safety and public library website filtering software) and the circumvention of copy protection mechanisms that have malfunctioned, have caused the instance of the work to become inoperable or which are no longer supported by their manufacturers.

Anticircumvention exemptions are generally seen to be be what?
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A: inefficient


Problem: New York City:

Manhattan's skyline, with its many skyscrapers, is universally recognized, and the city has been home to several of the tallest buildings in the world. As of 2011, New York City had 5,937 high-rise buildings, of which 550 completed structures were at least 330 feet (100 m) high, both second in the world after Hong Kong, with over 50 completed skyscrapers taller than 656 feet (200 m). These include the Woolworth Building (1913), an early gothic revival skyscraper built with massively scaled gothic detailing.

How many structures in New York City are over 100m tall?
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A: 550


Problem: Copper:

Copper, silver and gold are in group 11 of the periodic table, and they share certain attributes: they have one s-orbital electron on top of a filled d-electron shell and are characterized by high ductility and electrical conductivity. The filled d-shells in these elements do not contribute much to the interatomic interactions, which are dominated by the s-electrons through metallic bonds. Unlike metals with incomplete d-shells, metallic bonds in copper are lacking a covalent character and are relatively weak. This explains the low hardness and high ductility of single crystals of copper. At the macroscopic scale, introduction of extended defects to the crystal lattice, such as grain boundaries, hinders flow of the material under applied stress, thereby increasing its hardness. For this reason, copper is usually supplied in a fine-grained polycrystalline form, which has greater strength than monocrystalline forms.

What is copper normally missing?
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A:
unanswerable