The 22nd Amendment states that no person elected president and no person the office of president for more than two years. (Answer For #1)
"THE SIXTH AMENDMENT" guarantees the right to legal counsel at all significant stages of a criminal proceeding (Answer for #2)
The Seventeenth Amendment of the U.S Constitution was passed on "May 13, 1912" and Adopted or ratified on "April 8, 1913" (Answer for number #3)