The time (in minutes) that a subject spent on a psychological test was used as a measure of cognitive function. 41 schizophrenics (2) and 49 non-schizophrenics (1) were given the test, and their time was recorded. Psychologists theorize that the mean time on the test for non-schizophrenics will be less than the mean for schizophrenics. Which test should be used to test the theory that the mean time on the test for non-schizophrenics will be less than the mean for schizophrenics