The following table displays descriptive statistics on the participants involved in a study.

Characteristic

Experimental Medication

(n=100)

Placebo

(n=100)

Mean (SD) Age, years

47.2 (4.3)

46.1 (5.1)

% Males

46%

58%

Mean (SD) Educational Level, years

13.1 (2.9)

14.2 (3.1)

Mean (SD) Annual Income, $000s

$36.560 ($1,054)

$37.470 ($998)

Mean Body Mass Index

24.7 (2.7)

25.1 (2.4)

1. Generate a 95% confidence interval for the mean age among participants assigned to the placebo.
2. Generate a 95% confidence interval for the difference in mean ages in participants assigned to the experimental versus the placebo groups.
3. Generate a 95% confidence interval for the difference in mean body mass index in participants assigned to the experimental versus the placebo groups.