You wish to test the following claim ( ) at a significance level of . For the c

You wish to test the following claim (
) at a significance level of
. For the c

You wish to test the following claim (
) at a significance level of
. For the context of this problem,
where the first data set represents a pre-test and the second data set represents a post-test.

You believe the population of difference scores is normally distributed, but you do not know the standard deviation. You obtain pre-test and post-test samples for
subjects. The average difference (post – pre) is

with a standard deviation of the differences of
.
What is the test statistic for this sample? (Report answer accurate to three decimal places.)