With the dawn of which age did pitchblende, once considered almost worthless, become highly sought after as a source of uranium?

Which form of Chinese, the basis of the country's standard language, has more native speakers than any other language? Which convenience store chain, named for its original opening hours, began trading on the NYSE in July 2000 under the s… With reinforced hulls, the Coast Guard's Polar class cutters are which specialized vessels? With support from Andrew Jackson, which New Yorker was elected president in 1836? Which company's Mindstorms kits let builders create programmable robots, including Star Wars droids? Workplace safety laws were reformed after a March 1911 fire at which New York garment factory? Which song, written as a marching song during the French Revolution, later became France's national anthem? Which singer made his "Soul Patrol" fans proud when he won "American Idol" in 2006?