When the president lights the National Christmas Tree, a practice that has been going on since 1928, he or she is playing what presidential role?

If a survey researcher reports that her results are accurate within four percentage points, four percent is the

a. sampling frame b. stratum c. quota d. probability e. error of estimation

Which of the following countries is likely to be least affected by societal factors?

a. Russia. b. The United States. c. Great Britain. d. France.