For healthy women aged 18-24, systolic blood pressure readings (in millimeters of mercury) are normally distributed with a mean of 114.8 and a standard deviation of 13.1.
a. If a healthy woman is randomly selected from the general population of all women aged 18-24, find the probability of getting one with systolic blood pressure greater than 124.23.
b. If 16 women are randomly selected, find the probability that the mean of their systolic blood pressure readings is greater than 124.23.