please help with an explanation

AL LIMIT Question 5, 6.4.7-T HW Score: 36.67%, 3.67 of 10 Part 2 of 3 points x Points: 0 of 1 Save Assume that females have pulse rates that are normally distributed with a mean of u = 72.0 beats per minute and a standard deviation of o = 12.5 beats per minute. Complete parts (a) 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 0.4245 . (Round to four decimal places as needed.) b. If 16 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.)