5.4.2 In the study cited in Exercises 5.3.4 and 5.3.5, the calcium levels in men and women ages 60 years or older are summarized in the following table: Mean Standard Deviation Men 797 482 Women 660 414 Use these estimates as the mean m and standard deviation s for the U.S. populations for these age groups. If we take a random sample of 40 men and 35 women, what is the probability of obtaining a difference between sample means of 100 mg or more?

\f5.4.4 Given two normally distributed populations with equal means and variances of of = 240 and o? = 350, what is the probability that samples of size m = 40 and n2 = 35 will yield a value of X1 - x2 as large as or larger than 12?5.5.2 In the study cited in Exercise 5.5.1. 13 percent of the patients in the study reported previous episodes of stroke or transient ischemic attack. Use 13 percent as the estimate of the prevalence of stroke or transient ischemic attack within the population. If 70 subjects are chosen at random from the population, what is the probability that 10 percent or less would report an incidence of stroke or transient ischemic attack