The intelligence quotient (IQ) score, as measured by the Stanford-Binet IQ test, is normally distributed in a

Question:

The intelligence quotient (IQ) score, as measured by the Stanford-Binet IQ test, is normally distributed in a certain population of children. The mean IQ score is 100 points, and the standard deviation is 16 points. What percentage of children in the population have IQ scores
(a) 140 or more?
(b) 80 or less?
(c) Between 80 and 120?
(d) Between 80 and 140?
(e) Between 120 and 140?