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Vacuum is useful in a variety of processes and devices. Its first widespread use was in the incandescent light bulb to protect the filament from chemical degradation. The chemical inertness produced by a vacuum is also useful for electron beam welding, cold welding, vacuum packing and vacuum frying. Ultra-high vacuum is used in the study of atomically clean substrates, as only a very good vacuum preserves atomic-scale clean surfaces for a reasonably long time (on the order of minutes to days). High to ultra-high vacuum removes the obstruction of air, allowing particle beams to deposit or remove materials without contamination. This is the principle behind chemical vapor deposition, physical vapor deposition, and dry etching which are essential to the fabrication of semiconductors and optical coatings, and to surface science. The reduction of convection provides the thermal insulation of thermos bottles. Deep vacuum lowers the boiling point of liquids and promotes low temperature outgassing which is used in freeze drying, adhesive preparation, distillation, metallurgy, and process purging. The electrical properties of vacuum make electron microscopes and vacuum tubes possible, including cathode ray tubes. The elimination of air friction is useful for flywheel energy storage and ultracentrifuges.
What method of preserving food is dependant on using lightbulbs?
A: unanswerable

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Just as artist and inventor Leonardo da Vinci – partaking of the zeitgeist though not himself a humanist – advocated study of human anatomy, nature, and weather to enrich Renaissance works of art, so Spanish-born humanist Juan Luis Vives (c. 1493–1540) advocated observation, craft, and practical techniques to improve the formal teaching of Aristotelian philosophy at the universities, helping to free them from the grip of Medieval Scholasticism. Thus, the stage was set for the adoption of an approach to natural philosophy, based on empirical observations and experimentation of the physical universe, making possible the advent of the age of scientific inquiry that followed the Renaissance.
Who helped to further the movement closer to Scholasticism of the time?
A: unanswerable

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After gaining the Master Sword, Link is cleansed of the magic that kept him in wolf form, obtaining the Shadow Crystal. Now able to use it to switch between both forms at will, Link is led by Midna to the Mirror of Twilight located deep within the Gerudo Desert, the only known gateway between the Twilight Realm and Hyrule. However, they discover that the mirror is broken. The Sages there explain that Zant tried to destroy it, but he was only able to shatter it into fragments; only the true ruler of the Twili can completely destroy the Mirror of Twilight. They also reveal that they used it a century ago to banish Ganondorf, the Gerudo leader who attempted to steal the Triforce, to the Twilight Realm when executing him failed. Assisted by an underground resistance group they meet in Castle Town, Link and Midna set out to retrieve the missing shards of the Mirror, defeating those they infected. Once the portal has been restored, Midna is revealed to be the true ruler of the Twilight Realm, usurped by Zant when he cursed her into her current form. Confronting Zant, Link and Midna learn that Zant's coup was made possible when he forged a pact with Ganondorf, who asked for Zant's assistance in conquering Hyrule. After Link defeats Zant, Midna recovers the Fused Shadows, but destroys Zant after learning that only Ganondorf's death can release her from her curse. Returning to Hyrule, Link and Midna find Ganondorf in Hyrule Castle, with a lifeless Zelda suspended above his head. Ganondorf fights Link by possessing Zelda's body and eventually by transforming into a beast, but Link defeats him and Midna is able to resurrect Zelda.
Where is Link located after Zant's defeat?
A: unanswerable

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Instruments were marketed by teacher-dealers, much as the title character in the popular musical The Music Man. Often, these teacher-dealers conducted mandolin orchestras: groups of 4-50 musicians who played various mandolin family instruments. However, alongside the teacher-dealers were serious musicians, working to create a spot for the instrument in classical music, ragtime and jazz. Like the teacher-dealers, they traveled the U.S., recording records, giving performances and teaching individuals and mandolin orchestras. Samuel Siegel played mandolin in Vaudeville and became one of America's preeminent mandolinists. Seth Weeks was an African American who not only taught and performed in the United States, but also in Europe, where he recorded records. Another pioneering African American musician and director who made his start with a mandolin orchestra was composer James Reese Europe. W. Eugene Page toured the country with a group, and was well known for his mandolin and mandola performances. Other names include Valentine Abt, Samuel Adelstein, William Place, Jr., and Aubrey Stauffer.
Who played the mandolin in Vaudeville? 
A:
Samuel Siegel