The incubation time for Rhode Island Red chicks is normally distributed with a mean of 21 days and standard deviation of approximately 1 day. Answer the following questions. If 1000 eggs are being incubated, how many chicks do we expect will hatch?
a. In 19 to 23 days?
b. In 20 to 22 days?
c. In 21 days or fewer?
d. In 18 to 24 days? (Assume all eggs eventually hatch.)