Mrs. McGuffy is calculating a numerical analysis of the semester exam grades for students in her third period class. She entered the percentage correct on the exam for every student into a calculator and generated the following statistics. Which of these statements cannot be justified using statistics shown in these two calculator screen shots?
a) the range of the scores was 30%
b) the IQR was 8
c) the mean score was less than the median score?
d) the average score was 87%