2. Medical researchers took a random sample of 30 men from a list of 1274 volunteers. They put the men on a diet that restricted carbohydrate consumption to less than 20 grams per day for one year. They measured the men's systolic blood pressure at the beginning and at the end of the study. The average reduction in systolic blood pressure for the 30 men was 5.5 points. Assume that the population standard deviation is 1.8 points, and that the researchers hope to estimate the true mean reduction in systolic blood pressure. a. (0.25 points) State the research question. b. (0.25 points) State the parameter of interest. c. (1 point) Check the conditions needed for writing a valid confidence interval. There are three conditions. State each condition and whether it is met in this study. d. (1.5 points) Calculate a 90% confidence interval for the population mean. e. (1 point) Interpret the confidence interval in context.
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