Final answer:
If the president vetoes a bill and if the House and Senate repass the bill by a 2/3ds margin, the bill can become a law.
Step-by-step explanation:
If the president vetoes a bill and if the House and Senate repass the bill by a 2/3ds margin, the bill can become a law. According to the Constitution, if the president vetoes a bill, it must be passed again with a two-thirds majority vote in both the House of Representatives and the Senate for it to become a law. This override of a presidential veto requires a supermajority of 2/3 votes in both Houses.