Assigning Grades

IV. Assigning Grades. Professor CJ uses a normal distribution to assign grades in his Bio statistics class. He assigns an A to students scoring more than 2 standard deviations above the mean and an F to students scoring more than two standard deviations below the mean. He assigns a B to students who score between 1 and 2 standard deviations above the mean and a D to students who score 1 and 2 standard deviations below the mean. All other students get a C. what percent of the class receives each grade assuming the scores are normally distributed?