Dentists make many people nervous (even more so than statisticians!). To see whether such nervousness elevates blood pressure, the blood pressure and pulse rates of 60 subjects were measured in a dental setting and in a medical setting (“The Effect of the Dental Setting on Blood Pressure Measurement,” American Journal of Public Health [1983]: 1210– 1214). For each subject, the difference (dental-setting blood pressure minus medicalsetting blood pressure) was calculated. The analogous differences were also calculated for pulse rates. Summary data follows.

Mean Difference Standard Deviation of Differences Systolic Blood Pressure 4.47 8.77 Pulse (beats/min) 1.33 8.84

a. Do the data strongly suggest that true mean blood pressure is higher in a dental setting than in a medical setting? Use a level .01 test.

b. Is there sufficient evidence to indicate that true mean pulse rate in a dental setting differs from the true mean pulse rate in a medical setting? Use a significance level of .05.