D FA21.MATH122.143046.0C 2ND 12WI 0 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 n = 22 subjects. The average difference (post - pre) is d, = 7.7 with aIstandard deviation of the differences of sd = 13.3. What is the critical value for this test? (Report answer accurate to three decimal places.) What is the test statistic for this sample? (Report answer accurate to three decimal places.) The test statistic is... " in the critical region " not in the critical region This test statistic leads to a decision to... '\" reject the null accept the null "f fail to reject the null