The lengths of pregnancies are normally distributed with a mean of 268 days and a standard deviation of 6 days. A letter to "Dear Abby" inspired one classical use of the normal distribution. If we stipulate that a baby is premature if the length of pregnancy is in the lowest 4%, find the length of pregnancy that separates premature babies from those who are not premature. Premature babies often require special care, and this result could be helpful to hospital administrators in planning for that care.