A teacher figures that final grades in the chemistry department are distributed with 25% of students receiving an A, 25% of students receiving a B, 40% of students receiving a C, 5% of students receiving a D, and 5% of students receiving an F. At the end of a randomly selected semester, the following number of grades were recorded. Calculate the chi-square test statistic x to determine if the grade distribution for the department is different than expected. Use a = 0.01. Grade ABCDF Number 42 36 60 14 8 O A. 4.82 O B. 6.87 O C. 5.25 O D. 0.6375