Exercise 8.16 The diameter of a coronary vessel (bottom on a sample of 75 subjects) has a mean of x = 2.75 mm and a standard deviation of s = 0.45 mm. Suppose that the The diameter of this coronary vessel is normally distributed. (a) Give a 95% confidence interval for the average of the diameter population of this coronary vessel. (b) Give the standard error of the mean estimate. (c) Using the mean and standard deviation of the sample as the mean and standard deviation of the population, calculate the probability that the diameter of this coronary vessel is less than 2 mm.