Treating circulatory disease Angioplasty is a medical procedure in which an obstructed blood vessel is widened In some cases a wire mesh tube called a stent is placed in the vessel to help it remain open A study was conducted to compare the effectiveness of a bare metal stent with one that has been coated with a drug designed to prevent reblocking of the vessel A total of 5319 patients received bare metal stents and of these 837 needed treatment for reblocking within a year A total of 1126 received drug coated stents and 142 of them required treatment within a year Can you conclude that the proportion of patients who needed retreatment is less for those who received drug coated stents Let p denote the proportion of patients with bare metal stents who needed retreatment and p denote the proportion of patients with drug coated stents who needed retreatment Use the a 0 10 level of significance and the P value method with the TI 84 Plus calculator Part 0 4 Part 1 of 4 State the appropriate null and alternate hypotheses D D CO D O