The lengths of pregnancies are normally distributed with a mean of 267 days and a standard deviation of 15 days. a. Find the probability of a pregnancy lasting 307 days or longer. b. If the length of pregnancy is in the lowest 4%, then the baby is premature. Find the length that separates premature babies from those who are not premature Click to view page 1 of the table, Click to view page 2 of the table. a. The probability that a pregnancy will last 307 days or longer is 0.0038 . (Round to four decimal places as needed.) b. Babies who are born on or before days are considered premature (Round to the nearest integer as needed.)