Below are the final grades for Mrs. Stockton's class. What is the difference between the highest grade and the lowest grade?
A table with 2 columns, score and students. Row 1, score of 65.7 and 2 students. Row 2, score of 73.4 and 3 students. Row 3, score of 78.5 and 5 students. Row 4, score of 85.0 and 8 students. Row 5, score of 89.9 and 5 students. Row 6, score of 92.2 and 3 students. Row 7, score of 94.6 and 2 students.