What was a major feature of Roman architecture? A. greek columns

B. Roads

C. open theaters

D. arches and vaulted ceilings ​

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