Question

The scores on a chemistry exam were normally distributed with a mean of 65 and a standard deviation of 9
a. what percent of the students scored above 65?
b. what percent of the students scored above 56?
c. what percent of the students scored below 47?
d. what percent of the students scored between 65-74?
e. what percent of the students scored between 56-83?
f. if 1,000 students took the exam and all students with grades between 74 and 83 earned a B, how many students earned a B
g. how high must a student score in order to be in the top 2.5% of scores?