Background: The Beatles were an English rock band formed in Liverpool in 1960. With members John Lennon, Paul McCartney, George Harrison and Ringo Starr, they became widely regarded as the foremost and most influential music band. Rooted in skiffle, beat and 1950s rock and roll, the Beatles later experimented with several musical styles, ranging from pop ballads and Indian music to psychedelia and hard rock, often incorporating classical elements and unconventional recording techniques in innovative ways. In 1963 their enormous popularity first emerged as "Beatlemania"; as the group's music grew in sophistication, led by primary songwriters Lennon and McCartney, the band were integral to pop music's evolution into an art form and to the development of the counterculture of the 1960s.
Context: In Icons of Rock: An Encyclopedia of the Legends Who Changed Music Forever, Scott Schinder and Andy Schwartz describe the Beatles' musical evolution:  In their initial incarnation as cheerful, wisecracking moptops, the Fab Four revolutionised the sound, style, and attitude of popular music and opened rock and roll's doors to a tidal wave of British rock acts. Their initial impact would have been enough to establish the Beatles as one of their era's most influential cultural forces, but they didn't stop there. Although their initial style was a highly original, irresistibly catchy synthesis of early American rock and roll and R&B, the Beatles spent the rest of the 1960s expanding rock's stylistic frontiers, consistently staking out new musical territory on each release. The band's increasingly sophisticated experimentation encompassed a variety of genres, including folk-rock, country, psychedelia, and baroque pop, without sacrificing the effortless mass appeal of their early work.  In The Beatles as Musicians, Walter Everett describes Lennon and McCartney's contrasting motivations and approaches to composition: "McCartney may be said to have constantly developed - as a means to entertain - a focused musical talent with an ear for counterpoint and other aspects of craft in the demonstration of a universally agreed-upon common language that he did much to enrich. Conversely, Lennon's mature music is best appreciated as the daring product of a largely unconscious, searching but undisciplined artistic sensibility."  Ian MacDonald describes McCartney as "a natural melodist - a creator of tunes capable of existing apart from their harmony". His melody lines are characterised as primarily "vertical", employing wide, consonant intervals which express his "extrovert energy and optimism". Conversely, Lennon's "sedentary, ironic personality" is reflected in a "horizontal" approach featuring minimal, dissonant intervals and repetitive melodies which rely on their harmonic accompaniment for interest: "Basically a realist, he instinctively kept his melodies close to the rhythms and cadences of speech, colouring his lyrics with bluesy tone and harmony rather than creating tunes that made striking shapes of their own." MacDonald praises Harrison's lead guitar work for the role his "characterful lines and textural colourings" play in supporting Lennon and McCartney's parts, and describes Starr as "the father of modern pop/rock drumming".
Question: Why did they revolutionize the sound of rock and roll?
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Background: John Marshall (September 24, 1755 - July 6, 1835) was an American politician and the fourth Chief Justice of the United States (1801-1835). His court opinions helped lay the basis for United States constitutional law and many say he made the Supreme Court of the United States a coequal branch of government along with the legislative and executive branches. Previously, Marshall had been a leader of the Federalist Party in Virginia and served in the United States House of Representatives from 1799 to 1800. He was Secretary of State under President John Adams from 1800 to 1801 and, at the age of 45, became the last of the chief justices to be born in Colonial America.
Context: In 1797, Marshall accepted when President John Adams appointed him to a three-member commission to represent the United States to negotiate with France which, during the midst of its Revolutionary Wars, had seized neutral American merchant vessels. This had prompted the United States to appropriate funds to equip and man three frigates.  The other members of this commission were Charles Cotesworth Pinckney and Elbridge Gerry. However, when the envoys arrived in October 1797, they were kept waiting for several days, and then granted only a 15-minute meeting with French Foreign Minister Talleyrand. After this, the diplomats were met by three of Talleyrand's agents. Each refused to conduct diplomatic negotiations unless the United States paid enormous bribes, one to Talleyrand personally, and another to the Republic of France. The Americans refused to negotiate on such terms. Marshall and Pinckney returned home, while Gerry remained. This diplomatic scandal became known as the XYZ Affair, inflaming anti-French opinion in the United States. Marshall arrived in New York on June 17. His handling of the affair, as well as public resentment toward the French, made him popular with the American public. He opposed the Alien and Sedition Acts, enacted by the Federalists in response to the crisis.  In 1798, Marshall declined a Supreme Court appointment, recommending Bushrod Washington, who would later become one of Marshall's staunchest allies on the Court. In 1799, Marshall reluctantly ran for a seat in the United States House of Representatives. Although his congressional district (which included the city of Richmond) favored the Democratic-Republican Party, Marshall won the race, in part due to his conduct during the XYZ Affair and in part due to the support of Patrick Henry. His most notable speech was related to the case of Thomas Nash (alias Jonathan Robbins), whom the government had extradited to Great Britain on charges of murder. Marshall defended the government's actions, arguing that nothing in the Constitution prevents the United States from extraditing one of its citizens.  On May 7, 1800, President Adams nominated Congressman Marshall as Secretary of War. However, on May 12, Adams withdrew the nomination, instead naming him Secretary of State, as a replacement for Timothy Pickering. Confirmed by the United States Senate on May 13, Marshall took office on June 6, 1800. As Secretary of State, Marshall directed the negotiation of the Convention of 1800, which ended the Quasi-War with France and brought peace to the nation.  Elected as a delegate to the Virginia Constitutional Convention of 1829-1830, John Marshall advanced his view that the electorate should be expanded in Virginia by the provision that any white male who had served in the War of 1812 or who would serve in the militia in the future defense of the country deserved the right to vote.
Question: how old was he when he took office?
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