From which cultural hearth did the most crops spread outward

What event started the space race and made americans feel their security was threatened a.) alan shepard's suborbital flight. b.) the launch of sputnik c.) the launch of explorer d.) the cuban missle crisis

Examine this list of events that took place in china during the 20th century. which event or events could possibly have been a cause of the great leap forward? a. i only b. i, iii, and iv c. i and iii d. iii and iv

List 2 differences between the confederate and us constitution