A researcher randomly assigns 30 hypertensive participants to three groups of 10 each. Group 1 is taught muscle relaxation training; group 2 is taught cognitive relaxation training; group 3 is a...

A researcher randomly assigns 30 hypertensive participants to three groups of 10 each. Group 1 is taught muscle relaxation training; group 2 is taught cognitive relaxation training; group 3 is a no-treatment control. After the manipulation, blood pressure readings are taken on all participants. Blood pressure is represented by two numbers. The systolic blood pressure represents the maximum blood pressure at the point that the heart is actually beating. The diastolic blood pressure represents the minimum blood pressure between beats. Both are measured in terms of the number of millimeters of mercury that can be pushed up in a column by the pressure. The researcher wants to know (a) whether relaxation training reduces hypertension, and (b) whether one type of relaxation training is more effective than the other.