Scores of an IQ test have a bell-shaped distribution with a mean of 100 and a standard deviation of 18. Use the empirical rule to determine the following
(a) What percentage of people has an IQ score between 46 and 154?
(b) What percentage of people has an IQ score less than 64 or greater than 136?
(c) What percentage of people fas an IQ score greater than 136?