Scores on a difficult statistics exam have a mean of 60 and a standard deviation of 10. Complete parts a through e below. a. The teacher considers boosting the scores by adding 8 points to all exams. What is the mean and what is the standard deviation of the scores after the 8 points are added to each student's score? Mean = , standard deviation = (Type integers or decimals. Do not round.) b. Suppose instead the teacher considers increasing each student's score by 15%. What is the mean and what is the standard deviation of the adjusted scores now? Mean = , standard deviation = (Type integers or decimals. Do not round.)