Problem: Greece:

Internet cafes that provide net access, office applications and multiplayer gaming are also a common sight in the country, while mobile internet on 3G and 4G- LTE cellphone networks and Wi-Fi connections can be found almost everywhere. 3G/4G mobile internet usage has been on a sharp increase in recent years, with a 340% increase between August 2011 and August 2012. The United Nations International Telecommunication Union ranks Greece among the top 30 countries with a highly developed information and communications infrastructure.

Where does Greece rank in the work with communications?
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A: among the top 30 countries

Problem: Mandolin:

Some rock musicians today use mandolins, often single-stringed electric models rather than double-stringed acoustic mandolins. One example is Tim Brennan of the Irish-American punk rock band Dropkick Murphys. In addition to electric guitar, bass, and drums, the band uses several instruments associated with traditional Celtic music, including mandolin, tin whistle, and Great Highland bagpipes. The band explains that these instruments accentuate the growling sound they favor. The 1991 R.E.M. hit "Losing My Religion" was driven by a few simple mandolin licks played by guitarist Peter Buck, who also played the mandolin in nearly a dozen other songs. The single peaked at No. 4 on the Billboard Hot 100 chart (#1 on the rock and alternative charts), Luther Dickinson of North Mississippi Allstars and The Black Crowes has made frequent use of the mandolin, most notably on the Black Crowes song "Locust Street." Armenian American rock group System of A Down makes extensive use of the mandolin on their 2005 double album Mezmerize/Hypnotize. Pop punk band Green Day has used a mandolin in several occasions, especially on their 2000 album, Warning. Boyd Tinsley, violin player of the Dave Matthews Band has been using an electric mandolin since 2005. Frontman Colin Meloy and guitarist Chris Funk of The Decemberists regularly employ the mandolin in the band's music. Nancy Wilson, rhythm guitarist of Heart, uses a mandolin in Heart's song "Dream of the Archer" from the album Little Queen, as well as in Heart's cover of Led Zeppelin's song "The Battle of Evermore." "Show Me Heaven" by Maria McKee, the theme song to the film Days of Thunder, prominently features a mandolin.

What type of mandolin do rock musicians today use?
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A: single-stringed electric

Problem: Incandescent light bulb:

While inert gas reduces filament evaporation, it also conducts heat from the filament, thereby cooling the filament and reducing efficiency. At constant pressure and temperature, the thermal conductivity of a gas depends upon the molecular weight of the gas and the cross sectional area of the gas molecules. Higher molecular weight gasses have lower thermal conductivity, because both the molecular weight is higher and also the cross sectional area is higher. Xenon gas improves efficiency because of its high molecular weight, but is also more expensive, so its use is limited to smaller lamps.

How does the molecular weight of a gas relate to thermal conductivity?
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A: Higher molecular weight gasses have lower thermal conductivity

Problem: Richard Feynman:

Following the completion of his PhD in 1942, Feynman held an appointment at the University of WisconsinMadison as an assistant professor of physics. The appointment was spent on leave for his involvement in the Manhattan project. In 1945, he received a letter from Dean Mark Ingraham of the College of Letters and Science requesting his return to UW to teach in the coming academic year. His appointment was not extended when he did not commit to return. In a talk given several years later at UW, Feynman quipped, "It's great to be back at the only university that ever had the good sense to fire me."

Who told Feynman to never return to teaching?
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A:
unanswerable