1. A study was conducted to explore the relation between alcohol consumption and hypertension. 7400 nurses were surveyed and information about the amount of alcohol consumed per day (on average) and whether or not they suffered from hypertension was collected. The following table summarizes the information that was obtained.

Assuming the nurses surveyed were a random sample from the population of all nurses in the United States, we can use these data to test the null hypothesis H0 that there is no association between the row and column variables in this two-way table. The degrees of freedom for the X2 statistic for testing H0 is
A. 3.
B. 8.
C. 9.19.

2. A study was conducted to explore the relationship between a child's birth order and his or her chances of becoming a juvenile delinquent. The subjects were a random sample of girls enrolled in public high schools in a large city. Each subject filled out a questionnaire that measured whether or not they had shown delinquent behavior, and their birth order. The data are given in the table below.

Under the null hypothesis, the expected number of oldest children with delinquent behavior is
A. 27.75.
B. 37.12.
C. 154.5.