Historical data indicate that the standard deviation of a process is 6.3. A recent sample of size n = 28 produced a variance of 66.2. Use a significance level of 0.05 to test if the variance has increased. HO: 0^2 = 39.69 Ha: 0^2 > 39.69 o Since chi square test statistic =45.03 > chi square critical value =40.11, reject the null hypothesis. Since chi square test statistic =45.03 > chi square critical value =40.11, do not reject the null hypothesis. Since chi square test statistic -19.15 > chi square critical value =16.15, reject the null hypothesis. Since chi square test statistic = 19.15 > chi square critical value = 16.15, do not reject the null hypothesis