Question 962940
(A) H1: u is less than 1323 or greater than 1323
(D) It is common to use a 5 percent probability level for the test to reject the Ho and since we must consider statistical difference below and above the mean we use .05/2, that is the rejection region must be split between both tails of the distribution—0.025 in the upper tail and 0.025 in the lower tail—because your hypothesis specifies only a difference.
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The critical z‐scores for a probability of 0.025 in either tail to be –1.96 and 1.96. In order to reject the null hypothesis, the test statistic must be either smaller than –1.96 or greater than 1.96.
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The z-score for 1208 is -2.290 which is lower than the z-score of -1.96 so we would reject the Ho.  Again, this test uses the 5 percent probability since your problem does not include a statement of the probability level.
(E) The sample mean is statistically different from 1323.