Problem: Charleston, South Carolina:

By 1840, the Market Hall and Sheds, where fresh meat and produce were brought daily, became a hub of commercial activity. The slave trade also depended on the port of Charleston, where ships could be unloaded and the slaves bought and sold. The legal importation of African slaves had ended in 1808, although smuggling was significant. However, the domestic trade was booming. More than one million slaves were transported from the Upper South to the Deep South in the antebellum years, as cotton plantations were widely developed through what became known as the Black Belt. Many slaves were transported in the coastwise slave trade, with slave ships stopping at ports such as Charleston.

What year did the legal importation of slaves start?
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A: unanswerable


Problem: Capacitor:

If a capacitor is driven with a time-varying voltage that changes rapidly enough, at some frequency the polarization of the dielectric cannot follow the voltage. As an example of the origin of this mechanism, the internal microscopic dipoles contributing to the dielectric constant cannot move instantly, and so as frequency of an applied alternating voltage increases, the dipole response is limited and the dielectric constant diminishes. A changing dielectric constant with frequency is referred to as dielectric dispersion, and is governed by dielectric relaxation processes, such as Debye relaxation. Under transient conditions, the displacement field can be expressed as (see electric susceptibility):

What is it called when a dielectric constant changes with frequency?
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A: dielectric dispersion


Problem: Data compression:

A literature compendium for a large variety of audio coding systems was published in the IEEE Journal on Selected Areas in Communications (JSAC), February 1988. While there were some papers from before that time, this collection documented an entire variety of finished, working audio coders, nearly all of them using perceptual (i.e. masking) techniques and some kind of frequency analysis and back-end noiseless coding. Several of these papers remarked on the difficulty of obtaining good, clean digital audio for research purposes. Most, if not all, of the authors in the JSAC edition were also active in the MPEG-1 Audio committee.

What did these coders remark on?
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A: unanswerable


Problem: Pacific War:

By 1937, Japan controlled Manchuria and was ready to move deeper into China. The Marco Polo Bridge Incident on 7 July 1937 provoked full-scale war between China and Japan. The Nationalist and Communist Chinese suspended their civil war to form a nominal alliance against Japan, and the Soviet Union quickly lent support by providing large amount of materiel to Chinese troops. In August 1937, Generalissimo Chiang Kai-shek deployed his best army to fight about 300,000 Japanese troops in Shanghai, but, after three months of fighting, Shanghai fell. The Japanese continued to push the Chinese forces back, capturing the capital Nanking in December 1937 and committed which was known as Nanking Massacre. In March 1938, Nationalist forces won their first victory at Taierzhuang. but then the city of Xuzhou was taken by Japanese in May. In June 1938, Japan deployed about 350,000 troops to invade Wuhan and captured it in October. The Japanese achieved major military victories, but world opinion—in particular in the United States—condemned Japan, especially after the Panay Incident.

What was the capital of China?
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A:
Nanking