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The period saw several important technical innovations, like the principle of linear perspective found in the work of Masaccio, and later described by Brunelleschi. Greater realism was also achieved through the scientific study of anatomy, championed by artists like Donatello. This can be seen particularly well in his sculptures, inspired by the study of classical models. As the centre of the movement shifted to Rome, the period culminated in the High Renaissance masters da Vinci, Michelangelo and Raphael.
Along with da Vinci, who were two other artists regarded as masters of the High Renaissance?
A: Michelangelo and Raphael

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The U.S. War Department created the first antecedent of the U.S. Air Force in 1907, which through a succession of changes of organization, titles, and missions advanced toward eventual separation 40 years later. In World War II, almost 68,000 U.S airmen died helping to win the war; only the infantry suffered more enlisted casualties. In practice, the U.S. Army Air Forces (USAAF) was virtually independent of the Army during World War II, but officials wanted formal independence. The National Security Act of 1947 was signed on on 26 July 1947 by President Harry S Truman, which established the Department of the Air Force, but it was not not until 18 September 1947, when the first secretary of the Air Force, W. Stuart Symington was sworn into office that the Air Force was officially formed.
Who created the first version of the US Air Force in 1907?
A: U.S. War Department

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Hoover began using wiretapping in the 1920s during Prohibition to arrest bootleggers. In the 1927 case Olmstead v. United States, in which a bootlegger was caught through telephone tapping, the United States Supreme Court ruled that FBI wiretaps did not violate the Fourth Amendment as unlawful search and seizure, as long as the FBI did not break into a person's home to complete the tapping. After Prohibition's repeal, Congress passed the Communications Act of 1934, which outlawed non-consensual phone tapping, but allowed bugging. In the 1939 case Nardone v. United States, the court ruled that due to the 1934 law, evidence the FBI obtained by phone tapping was inadmissible in court. After the 1967 case Katz v. United States overturned the 1927 case that had allowed bugging, Congress passed the Omnibus Crime Control Act, allowing public authorities to tap telephones during investigations as long as they obtain a warrant beforehand.
What is now required to wire tap a citizen?
A: a warrant

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Returning home to Brantford after six months abroad, Bell continued his experiments with his "harmonic telegraph".[N 12] The basic concept behind his device was that messages could be sent through a single wire if each message was transmitted at a different pitch, but work on both the transmitter and receiver was needed.
For his system to work, Bell had to change what about each code?
A:
pitch