What was the main failure of the articles of confederation that eventually led to the us constitution

Which of the following would an isolationist support?

Awriter agreement is what ? a. contact b. investment c. solvency d. tariff

Which of these would be most useful in studying the effect of germs exchanged between the new and old worlds? a. a graph showing the number of europeans between 1492 and 1600. b. a graph showing the number of native americans between 1492 and 1600. c. a primary source description of the symptoms of an unknown disease affecting native americans in 1492. o d. a primary source description of the symptoms of an unknown disease affecting europeans in 1492.