Heart Rates For a certain group of individuals, the average heart rate is 72 beats per minute. Assume the variable is normally distributed and the standard deviation is 3 beats per minute. Ifa subject is selected at random! Find the probability that the person has the following heart rate. Round the nal answers to at least four decimal places and intermediate zvalue calculations to two decimal places. (a) Between 68 and 74 beats per minute P (68