Assume that the duration of human pregnancies can be described by a Normal model with mean 266 days and standard deviation 13 days a What percentage of pregnancies should last between 271 and 282 days b At least how many days should the longest 25 of all pregnancies last c Suppose a certain obstetrician is currently providing prenatal care to 51 pregnant patients Let y represent the mean length of their pregnancies According to the Central Limit Theorem what is the distribution of this sample mean y Specify the model mean and standard deviation d What s the probability that the mean duration of these patients pregnancies will be less than 255 days a The percentage of pregnancies that should last between 271 and 282 days is Round to two decimal places as needed b The longest 25 of all pregnancies should last at least Round to one decimal place as needed c Select the correct choice below and if necessary fill in the answer box es within your choice OA A Binomial model with trials and a probability of success of days Type integers or decimals rounded to two decimal places as needed OB A Normal model with mean and standard deviation Type integers or decimals rounded to two decimal places as needed OC There is no model that fits this distribution d The probability that the mean duration of these patients pregnancies will be less than 255 days is Round to four decimal places as needed