A set of final examination grades in an introductory statistics course is normally distributed with a means of 70 and a standard deviation of 10

c The probability is 5% that a student taking the test scores higher than what grade

d if the professor grades on a curve  gives A’s to the top 10% of the class regardless of the score are better off with a grade of 80 on this exam or a grade of 70 on a different exams where the mean is 60 and the standard deviation is 4