I'm pretty sure (1.) is A, and I know for a fact that (3.) is D because slavery was a regular practice between quarreling tribes. I have no clue what (2.) is. Best of luck.
Answer: 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.) This check prevents the President from blocking an act when significant support for it exists.
Explanation:
Noooooooooooooooooooooooooooo
