(A)Why is a "statistically significant difference" not necessarily a "practically important difference"? Use a relevant illustration to explain your answer.[10 marks]

(B)Suppose you always decide to reject the null hypothesis, regardless of any sample evidence. (i) What is the probability of a Type II error in such a case? (ii) Why is this a bad strategy to pursue?[15 marks]

(C) High blood pressure, if untreated, can lead to an increased risk of stroke and heart attack. A common definition of hypertension is a diastolic blood pressure of 90 or more. (i) State the null and alternative hypotheses for a physician who checks your blood pressure. (ii) Define the Type I and II errors for this case. What are the consequences of each?