1. A study is run to estimate the mean total cholesterol level in children 2-6 years of age. A sample of 9 participants is selected and their total cholesterol levels are measured as follows.

185 225 240 196 175 180 194 147 223

Generate a 95% confidence interval for the true mean total cholesterol levels in adults with a history of hypertension.

2. A clinical trial is planned to compare an experimental medication designed to lower blood pressure to a placebo. Before starting the trial, a pilot study is conducted involving 10 participants. The objective of the study is to assess how systolic blood pressure changes over time untreated. Systolic blood pressures are measured at baseline and again 4 weeks later. Compute a 95% confidence interval for the difference in blood pressures over 4 weeks.

Baseline 120 145 130 160 152 143 126 121 115 135

4 Weeks 122 142 135 158 155 140 130 120 124 130