The IQ test is designed in such a way that scores are normally distributed with mean u = 100 and standard deviation o= 15. a) What is the probability that someone has an IQ above 120? b) What is the probability that someone has an IQ below 90? c) What is the probability that someone has an IQ between 85 and 115? d) What is the minimum score a person must have to qualify among the top 5% of IQs?