You are interested in on-the-job anxiety among police officers and want to empirically test if the shift they work influences their anxiety. You hypothesize that there is a difference in anxiety on the job between police officers who work FIRST shift and police officers who work THIRD shift. You collect data from a large random sample of officers from both shifts. You find that the average on-the-job anxiety for officers who work FIRST shift is 12.8 (std dev = 2.76), whereas the average for officers who work THIRD shift is 8.8 (std dev = 2.85). Your obtained value is 12.461. The critical t value is 1.97 at the .05 level of significance. You decide to:

a. Reject the null hypothesis that there is no difference between the on-the-job anxiety of FIRST and THIRD shift police officers based on a one-tailed negative test.

b. Reject the null hypothesis that there is no difference between the on-the-job anxiety of FIRST and THIRD shift police officers based on a one-tailed positive test.

c. Reject the null hypothesis that there is no difference between the on-the-job anxiety of FIRST and THIRD shift police officers based on a two-tailed nondirectional hypothesis. d.Fail to reject the null hypothesis that there is no difference between the on-the-job anxiety of FIRST and THIRD shift police officers based on a two-tailed nondirectional test.