The lengths of a particular animal's pregnancies are approximately normally distributed, with mean p = 273 days and standard deVIatIon a = 12 days. (a) What proportion of pregnancies lasts more than 291 days? (b) What proportion of pregnancies lasts between 264 and 276 days? (c) What Is the probability that a randomly selected pregnancy lasts no more than 249 days? (d) A" very preterm" baby Is one whose gestation period Is less than 255 days. Are very preterm babies unusual? a Click the icon to view a table of areas under the normal curve. (a) The proportion of pregnancies that last more than 291 days is I]. (Round to four decimal places as needed.) (b) The proportion of pregnancies that last between 264 and 276 days is E. ' (Round to four decimal places as needed.) (c) The probability that a randomly selected pregnancy lasts no more than 249 days is D. (Round to four decimal places as needed.) (d) A "very preterm" baby is one whose gestation period is less than 255 days. Are very preterm babies unusual? The probability of this event' Is D so it\" - be unusual because the probability rs - \"than 0.05. (Round to tour decimal places as needed.)