The date of births in humans is approximately normally distributed with a mean at 280 days gestation (this is the so-called "due date") and a standard deviation of 8 days. Suppose that a pregnant woman will have a scheduled cesarean section to deliver her baby.
Determine how many days before the due date the cesarean section should be carried out so that there is no more than a 10 percent chance that the woman will go into labor before that date.

Question 2

Studies have found that the distribution of the wingspan of bald eagles is approximately normal with a mean of 80 inches and a standard deviation of 4 inches.

Part (a) What is the probability that a randomly selected eagle's wingspan is exactly 77 inches? Explain your answer.

Part (b) What is the probability that a randomly selected eagle's wingspan is 77 inches or less?

Part (c) What is the probability that a randomly selected eagle's wingspan is 80 inches or more?

Part (d) Which of the following events is more likely: That a randomly selected eagle's wingspan is greater than 83 inches or that a randomly selected eagle's wingspan is less than 78 inches. Explain how you find your answer.