State College y! Yahoo 9.5 Hypothesis Testing for Mean o Unknown Using the Critical Value and Rejection Region (t-test) You wish to test the following claim (Ha) at a significance level of a = 0.02. Ho:u = 74.3 Ha: u # 74.3 You believe the population is normally distributed, but you do not know the standard deviation. You obtain a sample of size n = 40 with a mean of @ = 65.5 and a standard deviation of s = 20.5. a.) This test is left-tailed right-tailed two-tailed b. ) At a = 0.02, the critical value = (use 3 decimal places) c.) The test statistic = (use 2 decimal places) d. ) The test statistic is... O in the critical region O not in the critical region e.) This test statistic leads to a decision to... O reject the null hypothesis O accept the null hypothesis O fail to reject the null hypothesis f.) As such, the final conclusion is that... There is sufficient evidence to warrant rejection of the claim that the population mean is not equal to 74.3