What are the two formal duties of the vice president? what are the three parts of the executive branch? what were the constitutional changes to the presidency?

The three parts of the Executive Branch include the President, the Cabinet and the independent agencies. The Vice President is the stand in for the president in ceremonial roles. He also serves as the presiding officer of the U.S. Senate. Several amendments have been added to the U.S. Constitution to further define the powers of the president. Among them are the Twelfth Amendment (1804), which provides the procedure for electing the President and the Vice-President. The Twentieth Amendment (1933) changed the presidential inauguration from March to January. The Twentieth Second Amendment (1951) limits the number of terms a president can serve to two terms. The Twenty Fifth Amendment (1967) established procedures to address  vacancy in either the presidential or vice-presidential offices. The Presidential Succession Act (1947) defines the officials who can succeed to the presidency after the Vice-President.

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