In the study cited in Exercise 5.3.4, researchers found the mean sodium intake in men and women 60 years or older to be 2940 mg with a standard deviation of 1476 mg. Use these values for the mean and standard deviation of the U.S. population and find the probability that a random sample of 75 people from the population will have a mean:

(a) Less than 2450 mg

(b) Over 3100 mg

(c) Between 2500 and 3300 mg

(d) Between 2500 and 2900 mg