Use the Following Information to Answer Questions (5) - (7)

question 37

Multiple Choice

Use the following information to answer questions (5) - (7) . A tire manufacturer has made some
modifications to its most popular tire and wants to see if the tread on the modified tire will last
longer than the original tire. Because there is much variation in the way people drive, the
manufacturer decides to use blocking to reduce this variation. Twenty cars will be used to test the
tires. Ten cars are randomly selected to receive an original tire on the right rear wheel and a
modified tire on the left rear wheel. The remaining ten cars will receive an original tire on the left
rear wheel and a modified tire on the right rear wheel. Each car will then be driven 10,000 miles and
the amount of wear recorded for each wheel.
-Was the study described above most likely an observational study or a controlled experiment?

• A)Experimental because the researchers placed both types of tires on each car, randomly assigning one type of tire to the right side and the other type to the left side.
• B)Experimental because the researcher could not control how fast each car was driven.
• C)Observational study because the researcher decided which car received which type of tire.
• D)Observational study because the tires were not a random sample.

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Definitions:

Darwin

Refers to Charles Darwin, a 19th-century naturalist known for proposing the theory of evolution by natural selection.

Facial Expressions

Movements of the facial muscles that convey emotions or reactions, serving as nonverbal communication among humans.

Eibl-Eibesfeldt

Pertains to Irenäus Eibl-Eibesfeldt, a renowned ethologist notable for his contributions to the study of human behavior and evolution.

Human Nature

The inherent characteristics, including ways of thinking, feeling, and acting, that all humans are said to possess.