4. Data from a random sample of 50 students in a school district showed a positive relationship between reading score on a standardized reading exam and shoe size. Can it be
concluded that having bigger feet causes one to have a higher reading score? Explain your answer.
Use the following scenarios for Problems 5–7.
A. Researchers want to determine if there is a relationship between whether or not a woman smoked during pregnancy and the birth weight of her baby. Researchers examined records
for the past five years at a large hospital.
B. A large high school wants to know the proportion of students who currently use illegal drugs. Uniformed police officers asked a random sample of 200 students about their drug use.
C. A company develops a new dog food. The company wants to know if dogs would prefer its new food over the competition’s dog food. One hundred dogs, who were food deprived
overnight, were given equal amounts of the two dog foods: the new food versus the competitor’s food. The proportion of dogs preferring the new food versus the competitor’s was
recorded.