The lengths of pregnancies are normally distributed with a mean of 268 days and a standard deviation of 15 days. a. In a letter to an advice column, a wife claimed to have given birth 307 days after a brief visit from her husband, who was working in another country. Find the probability of a pregnancy lasting 307 days or longer. What does the result suggest? b. If the length of pregnancy is in the lowest 3%, then the baby is premature. Find the length that separates premature babies from those who are not considered premature