A recent study of the hourly wages of maintenance crew members for major airlines showed that the mean hourly salary was $20.50, with a standard deviation of $3.50. Assume the distribution of hourly wages follows the normal probability distribution. If we select a crew member at random, what is the probability the crew member earns:
a. Between $20.50 and $24.00 per hour?
b. More than $24.00 per hour?
c. Less than $19.00 per hour?