Please help me with this problem, I've had no luck.

Assume that females have pulse rates that are normally distributed with a mean of p = 73.0 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 less than 76 beats per minute. The probability is 0.5948 . (Round to four decimal places as needed.) b. If 4 adult females are randomly selected, find the probability that they have pulse rates with a mean less than 76 beats per minute. The probability is]. (Round to four decimal places as needed.)