I'm struggling with the second part of this questions.

Assume that females have pulse rates that are normally distributed with a mean of p = 72.0 beats per minute and a standard deviation of o = 12.5 beats per minute. through (c) below. a. If 1 adult female is randomly selected, find the probability that her pulse rate is between 65 beats per minute and 79 beats per minute. The probability is .4245 . (Round to four decimal places as needed.) b. If 25 adult females are randomly selected, find the probability that they have pulse rates with a mean between 65 beats per minute and 79 beats per minute. The probability is | (Round to four decimal places as needed.)