Compare the means of two populations using 96 percent confidence interval.
In order to evaluate the means of two populations, independent random samples of 484 observations are selected from each population, with the following results:
Sample 1

Sample 2

xi

x_{2}

st = 105

s_{2} = 165

(a) Utilize a 96 percent confidence interval to estimate the difference between the population means (mean 1  mean 2)
(b) Test the null hypothesis: Ho: (mean 1  mean 2) = 0 versus the alternative hypothesis: H_{a} : mean 1  mean 2) is not equal to 0. Using alpha = 0.04, give the following:
1. The test statistic z=
2. positive critical z score the negative critical z score
® : Test the null hypothesis: Ho: (mean 1  mean 2) = 21 versus the alternative hypothesis: Ha: (mean 1  mean 2) not equal to 21. Using alpha = 0.04, give the following.
1. Test statistic
2. positive critical z score
3.the negative critical z score