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In November 1997, the website mp3.com was offering thousands of MP3s created by independent artists for free. The small size of MP3 files enabled widespread peer-to-peer file sharing of music ripped from CDs, which would have previously been nearly impossible. The first large peer-to-peer filesharing network, Napster, was launched in 1999.
Which website offered MP3s for free?
A: mp3.com

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Following Kammu's death in 806 and a succession struggle among his sons, two new offices were established in an effort to adjust the Taika-Taihō administrative structure. Through the new Emperor's Private Office, the emperor could issue administrative edicts more directly and with more self-assurance than before. The new Metropolitan Police Board replaced the largely ceremonial imperial guard units. While these two offices strengthened the emperor's position temporarily, soon they and other Chinese-style structures were bypassed in the developing state. In 838 the end of the imperial-sanctioned missions to Tang China, which had begun in 630, marked the effective end of Chinese influence. Tang China was in a state of decline, and Chinese Buddhists were severely persecuted, undermining Japanese respect for Chinese institutions. Japan began to turn inward.
In what year did Emperor Kanmu die?
A: 806

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Chromobacterium violaceum and Pseudomonas fluorescens can both mobilize solid copper, as a cyanide compound. The ericoid mycorrhizal fungi associated with Calluna, Erica and Vaccinium can grow in copper metalliferous soils. The ectomycorrhizal fungus Suillus luteus protects young pine trees from copper toxicity. A sample of the fungus Aspergillus niger was found growing from gold mining solution; and was found to contain cyano metal complexes; such as gold, silver, copper iron and zinc. The fungus also plays a role in the solubilization of heavy metal sulfides.
What fungus helps to toxify heavy metal sulfides?
A: unanswerable

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In 1948, the point-contact transistor was independently invented by German physicists Herbert Mataré and Heinrich Welker while working at the Compagnie des Freins et Signaux, a Westinghouse subsidiary located in Paris. Mataré had previous experience in developing crystal rectifiers from silicon and germanium in the German radar effort during World War II. Using this knowledge, he began researching the phenomenon of "interference" in 1947. By June 1948, witnessing currents flowing through point-contacts, Mataré produced consistent results using samples of germanium produced by Welker, similar to what Bardeen and Brattain had accomplished earlier in December 1947. Realizing that Bell Labs' scientists had already invented the transistor before them, the company rushed to get its "transistron" into production for amplified use in France's telephone network.
When did Heinrich Welker start researching electronics?
A:
unanswerable