試題詳解

9.We have a population that is normally distributed with an unknown variance. A two-tailed hypothesis test was conducted for the population mean. A random sample of size 22 was selected. After setting the level of significance, a, a student wrongly used as the critical value and concluded to reject the null hypothesis. If the student did not make the mistake, what would be the correct conclusion?
(A)The conclusion stays the same, that is, the null hypothesis should be rejected;
(B)The conclusion is different, that is, the null hypothesis should not be rejected;
(C) There is insufficient information to make a conclusion. In other words, the null hypothesis may or may not be rejected;
(D) None of the above.