Could you please show me all of your work?

A research wants to know if negative perceptions of mental illness will change after taking Professor Gann's Mental Health and Criminal Justice course. Prior to the course, Prof. G. surveyed 8 (willing) students about their perceptions of violence among those who have been diagnosed with a mental disorder using a 5 question survey with a scale from 1 (not very violent) to 5 (very violent). She added up the scores across all 5 questions are compiled a Mental Health Perceptions (MHP) score. After the same students took the course, Prof. G. re-surveyed the students with the same questionnaire. Below are the scores on the perception of mental illness and violence before and after the course. The highest a student could score is a 25, and the lowest was 5: MHP Before Course MHP After Course 21 15 19 11 12 8 5 5 CO 6 7 8 5 20 12 You want to know if there is a significant difference between the scores for the students. To test this, use the .05 level of confidence. What is the calculated statistic and what can you conclude about Prof. G.'s research