A machine produce metal rods used in an automobile suspension system. A random sample of 6 rods is selected and diameter is measured. The measuring data( in millimeters) are as follows. Assuming that the sample drawn from the normally distributed population.

8.24

8.26

8.20

8.28

8.21

8.23

Find 95% two sided confidence interval on the mean rod diameter, and interpret the result with reference to the given problem.