(a) Ho : 0D =0, Ha : 0D

Test Stat = = -13.142 Rejection region : T test < TOM) df_19 = -2.539 p - value = 13.142) = 5.49 * 10-11 0.01 so, we reject null and conclude yes there is decrease in mortality rate. (b) rejection region: D < 2.539 * (14.20/sqrt(20)) = -8.062 -10) -8.062 + 10 ) = 0.7256 14.20/sqrt(20) power = 72.56%, Type II error = 1 Power = 0.2744 (c) = 2.86, C'l: (D 2.86* (SD/v6)) = (-41.73 2.86* (14.2/sqrt(20))) = (-50.81, -32.65) interpret : u'e are 99% confident that the true mean change is contained inside the above interval. (d) Assumption made is that the variation in heart disease mortality is uniform across all state in US.