Final answer:
In order for Congress to override a presidential veto, a two-thirds vote of both houses of Congress is required.
Step-by-step explanation:
In order for Congress to override a presidential veto, a two-thirds vote of both houses of Congress is required. This means that two-thirds of the members in both the House of Representatives and the Senate must vote in favor of overriding the veto. A simple majority is not sufficient, and unanimity is not needed.
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