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Built around 1915, the Alaska Railroad (ARR) played a key role in the development of Alaska through the 20th century. It links north Pacific shipping through providing critical infrastructure with tracks that run from Seward to Interior Alaska by way of South Central Alaska, passing through Anchorage, Eklutna, Wasilla, Talkeetna, Denali, and Fairbanks, with spurs to Whittier, Palmer and North Pole. The cities, towns, villages, and region served by ARR tracks are known statewide as "The Railbelt". In recent years, the ever-improving paved highway system began to eclipse the railroad's importance in Alaska's economy.

What year was the Alaska Railroad built?
Answer: around 1915
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Secretary of War Elihu Root (18991904) led the modernization of the Army. His goal of a uniformed chief of staff as general manager and a European-type general staff for planning was stymied by General Nelson A. Miles but did succeed in enlarging West Point and establishing the U.S. Army War College as well as the General Staff. Root changed the procedures for promotions and organized schools for the special branches of the service. He also devised the principle of rotating officers from staff to line. Root was concerned about the Army's role in governing the new territories acquired in 1898 and worked out the procedures for turning Cuba over to the Cubans, and wrote the charter of government for the Philippines.

Which military academy did Root help grow?
Answer: West Point
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The thermionic triode, a vacuum tube invented in 1907, enabled amplified radio technology and long-distance telephony. The triode, however, was a fragile device that consumed a lot of power. Physicist Julius Edgar Lilienfeld filed a patent for a field-effect transistor (FET) in Canada in 1925, which was intended to be a solid-state replacement for the triode. Lilienfeld also filed identical patents in the United States in 1926 and 1928. However, Lilienfeld did not publish any research articles about his devices nor did his patents cite any specific examples of a working prototype. Because the production of high-quality semiconductor materials was still decades away, Lilienfeld's solid-state amplifier ideas would not have found practical use in the 1920s and 1930s, even if such a device had been built. In 1934, German inventor Oskar Heil patented a similar device.

When was the thermionic triode invented?
Answer:
1907