Title: 1966 in the United States
Content: President: Lyndon B. Johnson (D-Texas) ; Vice President: Hubert Humphrey (D-Minnesota) ; Chief Justice: Earl Warren (California) ; Speaker of the House of Representatives: John William McCormack (D-Massachusetts) ; Senate Majority Leader: Mike Mansfield (D-Montana) ; Congress: 89th  {| class="wikitable collapsible collapsed" ! Governors and Lieutenant Governors
Title: 6th United States Congress
Content: President: Thomas Jefferson (DR) ; President pro tempore: Samuel Livermore (F), elected December 2, 1799 ; Uriah Tracy (F), elected May 14, 1800 ; John E. Howard, (F), elected November 21, 1800 ; James Hillhouse, (F), elected February 28, 1801 
Title: 26th United States Congress
Content: President: Richard M. Johnson (D) ; President pro tempore: William R. King (D) 
Title: 36th United States Congress
Content: President: John C. Breckinridge (D) ; President pro tempore: Benjamin Fitzpatrick (D), until February 26, 1860 ; Jesse D. Bright (D), June 12–13, 1860 ; Benjamin Fitzpatrick (D), June 26, 1860 – December 2, 1860 ; Solomon Foot (R), elected February 16, 1861 
Title: 1960 in the United States
Content: President: Dwight D. Eisenhower (R-Kansas/Pennsylvania) ; Vice President: Richard Nixon (R-California) ; Chief Justice: Earl Warren (California) ; Speaker of the House of Representatives: Sam Rayburn (D-Texas) ; Senate Majority Leader: Lyndon B. Johnson (D-Texas) ; Congress: 86th  {| class="wikitable collapsible collapsed" ! Governors and Lieutenant Governors
Title: 1964 in the United States
Content: President: Lyndon B. Johnson (D&ndash;Texas) ; Vice President: vacant ; Chief Justice: Earl Warren (California) ; Speaker of the House of Representatives: John William McCormack (D&ndash;Massachusetts) ; Senate Majority Leader: Mike Mansfield (D&ndash;Montana) ; Congress: 88th  {| class="wikitable collapsible collapsed" ! Governors and Lieutenant Governors
Title: 1968 in the United States
Content: President: Lyndon B. Johnson (D-Texas) ; Vice President: Hubert Humphrey (D-Minnesota) ; Chief Justice: Earl Warren (California) ; Speaker of the House of Representatives: John William McCormack (D-Massachusetts) ; Senate Majority Leader: Mike Mansfield (D-Montana) ; Congress: 90th  {| class="wikitable collapsible collapsed" ! Governors and Lieutenant Governors
Title: 6th United States Congress
Content:  The 6th United States Congress was a meeting of the legislative branch of the United States federal government, consisting of the Senate and the House of Representatives. It met at Congress Hall in Philadelphia, Pennsylvania and in Washington, D.C. from March 4, 1799, to March 4, 1801, during the last two years of John Adams's presidency. It was the last Congress of the 18th century and the first to convene in the 19th. The apportionment of seats in House of Representatives was based on the First Census of the United States in 1790. Both chambers had a Federalist majority. This was the last Congress in which the Federalist Party controlled the presidency or either chamber of Congress.
Title: 1969 in the United States
Content: President: Lyndon B. Johnson (D&ndash;Texas) (until January 20), Richard Nixon (R&ndash;California) (starting January 20) ; Vice President: Hubert Humphrey (D&ndash;Minnesota) (until January 20), Spiro Agnew (R&ndash;Maryland) (starting January 20) ; Chief Justice: Earl Warren (California) (until June 23), Warren E. Burger (Minnesota) (starting June 23) ; Speaker of the House of Representatives: John William McCormack (D&ndash;Massachusetts) ; Senate Majority Leader: Mike Mansfield (D&ndash;Montana) ; Congress: 90th (until January 3), 91st (starting January 3)  {| class="wikitable collapsible collapsed" ! Governors and Lieutenant Governors
Title: 39th United States Congress
Content: President: Andrew Johnson (D), until April 15, 1865; vacant thereafter. ; President pro tempore: Lafayette S. Foster (R), until March 2, 1867 ; Benjamin F. Wade (R), elected March 2, 1867 ; Republican Conference Chairman: Henry B. Anthony 

Question: who is the sixth president of the united states?
Answer: John Quincy Adams.