A researcher is interested in the relationship between # of minutes/day of aerobic exercise (e.g., jogging, biking) and how alert people feel. He surveys 8 adults and asks them to report their daily minutes of exercise and how alert they feel on an interval scale of 1-10 (where 1-not at all alert and 10=extremely alert). Participant Min of exercise (X) Alertness Score (Y) 25 0 30 15 1 2 3 4 5 6 7 8 45 60 0 20 3 3455 00 6N 3 8 2 The Pearson correlation coefficient (r) between exercise and alertness is +0.722 a) What is the regression equation in this example? b) What is the predicted alertness score for anyone who exercises 30 minutes per day? c) What is the average error in your predictions (i.e., S.)? d) What is the proportion of variance in alertness that is accounted for by exercise in this example?