To find mean, standard deviation and confidence interval.
Consider the following data for two independent random samples taken from two normal populations.
Sample 1:

10

7

13

7

9

8

Sample 2:

8

7

8

4

6

9

a. work out the two sample means.
b. find out the two standard deviations
c. what is the point estimate of the difference between the two population means?
d. what is the 90 percent confidence interval estimate of the difference between two population means.