1. A clinical trial is run to assess the effectiveness of a new drug in lowering blood pressure. Patients are randomized to receive the new drug or placebo and systolic blood pressure is measured after 12 weeks on the assigned treatment. Is the mean systolic blood pressure for patients in the new drug group significantly lower than the mean systolic blood pressure for patients in the placebo group after the 12 week treatment?

Sample Size Mean Std Dev New Drug1 15 118.2 14.3 Placebo, 15 122.6 15.1