Problem 2, IQ tests part 2 [3 points]

In the Normal model N(100, 15) from Problem 1, what cutoff value(s) bounds

(a) the highest 15 % of all IQs?

(b) the lowest 30 % of the IQs?

(c) the middle 65 % of the IQs?

Problem 3, IQ tests part 3 [3 points] Consider the IQ model N(100, 15) one last time.

(a) What IQ represents the 20th percentile?

(b) What IQ represents the 97th percentile?

(c) What is the IQR of the IQs