1. A researcher wanted to examine the effects of a new potassium supplement on blood pressure. They ask you to develop their study design.
   1. How would you design a study to examine whether this new potassium supplement can decrease blood pressure for adults in the United States? Why?
   2. How would you better design the study to exclude the influence of age, gender and race? Why?
   3. How would you study the relationship between potassium intake and blood pressure in the general population if experiments were not viable? Explain your rationale.