The mean incubation time for a type of fertilized egg kept at 100.5°F is 23 days. Suppose that the incubation times are approximately normally distributed with a standard deviation of 1 day.
(a) What is the probability that a randomly selected fertilized egg hatches in less than 21 days?
(b) What is the probability that a randomly selected fertilized egg hatches between 22 and 23 days?
(c) What is the probability that a randomly selected fertilized egg takes over 25 days to hatch?