How can congress pass a law over a president veto

By threatening a veto, the President can persuade legislators to alter the content of the bill to be more acceptable to the President. Congress can override a veto by passing the act by a two-thirds vote in both the House and the Senate. (Usually an act is passed with a simple majority.)

Explanation:

they need to get a 2/3 majority in both the house and the senate.

Explanation:

nafta and the union are used as a trade between other countries these   organizations are used as spokes person for the country

yes i think there would be volunteers