Suppose that the average for students who graduate are normally distributed with a population mean of 70 and a population standard deviation of 13. 50% of the students have both Facebook and Instagram accounts.

a) The "middle" 95% of all students have average scores between __ and ___?

b) What proportion of students have average scores between 60 and 75?

c) Calculate the 14th percentile.

d) Calculate the 92nd percentile.