The answers can only be national government or state government or both
1. declare and engage in war - national
2. conduct elections - state
3. print and coin money - national
4. govern marriage laws - state
5. maintain an army, navy, and air force - national
6. regulate interstate and foreign commerce - national
7. regulate intrastate commerce - state
8. punish lawbreakers - both
9. levy and collect taxes - both
10. protect the rights of citizens - both
11. set traffic standards - state
12. admit new states - national
13. provide for public safety - both
14. borrow money - both
15. establish and maintain schools - state
16. negotiate treaties with foreign countries - national
17. protect public health - both
18. determine the qualification of voters - state
19. set up a post office - national
20. set rules for immigration - national
21. maintain the state militia (also known as the National Guard) - state