Article V of US Constitution describes the method of introducing an amendment in the constitution. For an amendment to be instituted, it has to be approved by both houses of US Congress with a two third majority. An amendment approved in such a manner does not require President's approval and is directly sent to states for ratification.
No. He could only suggest that Congress introduce one.
Ratification
No - the president has no official role in the amendment process.
Only the States can ratify a constitutional amendment. The President can veto legislation putting the amendment up for ratification, but can be overridden by the normal process in the Senate.
constitutional amendment that created separate ballots for the president and vice president
The 12th Amendment reorganized the system for electing the US President.
The Twelfth Amendment (Amendment XII) to the United States Constitution provides the procedure by which the President and Vice President are elected.
25th Amendment to the U. S. Constitution
A Constitutional amendment to clarify the way votes are cast in the Electoral College was necessary because it was unclear as to which votes were for the president and which votes were for the vice president. This was accomplished through the Twelfth Amendment.
After President Lincoln issued the Emancipation Proclamation, the Thirteenth Amendment abolished slavery in the United States.
What is the "constitutional orphan" of the Tenth Amendment?
Yes. The Twenty-Second Amendment, ratified in 1951, limits the US President to two terms of office.
James Madison
Structure of the Federal Government