Which hypothesis testing you should perform in the following situation. - State null hypotheses and test statistics

a) You investigated the effect of a new medicine upon hypertension. A medical assistant sampled the blood pressures of 20 randomly selected patients with high blood pressure before and after they receive a dose of a new medicine. b) You investigated the effect of a new medicine upon hypertension. A researcher gave one group of people an active drug and gave a different group of people an inactive placebo, then compare the blood pressures between the groups.

c) You want to test the hypothesis that eating fish makes one smarter. A random sample of 12 persons take a fish oil supplement for one year and then are given an IQ test.