Suppose we want to test the claim that heavy marijuana use has a greater effect on mental abilities than light marijuana users. For the study, 64 light marijuana users were tested on the number of items they could sort and the mean was 53.3 and the standard deviation was 3.6. Then 65 heavy marijuana users were tested and the mean number of items sorted was 51.3 and the standard deviation was 4.5. Do these results suggest that the mean for heavy marijuana users was lower than for light marijuana users? Test the claim using a= .05, using p-value method.