Which event marked the end of cultural and economic unity along the silk road?
a. the rise of the byzantine empire
b. the fall of the mongol empire
c. the children's crusade
d. the battle of hastings

Identify the example of when situation and time are key to assessing risk of harm in a research study: a study on the efficacy of a behavioral intervention for smoking cessation involves both adults and teenagersasking women if they have had an abortionresearch on the prevalence of hiv-infected individuals in communitiesa survey about sexually transmitted diseases