What was one key feature of the United States during the Cold War? A. An economic system based on communism
B. An economic system based on capitalism
C. A government led by a dictator
D. A government that did not allow voting

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.