3] A researcher wants to test three different techniques for lowering blood pressure in people who have high blood pressure. The subjects are divided into three groups at random: the first group is given medication, the second group exercises, and the third group follows a special diet. Each person's blood pressure is measured after four weeks to see how much it has dropped. Test the claim that there is no signicant difference between the means at a=0.05. (6 marks] Medication Exercise 10 6 1 2 9 15 13