Assume that females have pulse rates that are normally distributed with a mean of =75.0 beats per minute and a standard deviation of =12.5 beats per minute. Complete parts(a) through(c) below.

a. If 1 adult female is randomlyselected, find the probability that her pulse rate is less than 78 beats per minute.

b. If 4 adult females are randomlyselected, find the probability that they have pulse rates with a mean less than 78 beats per minute.

c. Why can the normal distribution be used in part(b), even though the sample size does not exceed30?