Durations of human pregnancies are normally distributed with a mean of 268 days and a standard deviation of 15 days. c. Durations of human pregnancies are normally distributed with a mean of 268 days...

Durations of human pregnancies are normally distributed with a mean of 268 days and a standard deviation of 15 days.

c.         Durations of human pregnancies are normally distributed with a mean of 268 days and a standard deviation of 15 days

d. What percentage of women have a pregnancy lasting less than or equal to 238 days?