Question: A gasoline company has developed a new additive for gasoline that is supposed to improve the gas mileage of a car. A consumer organization has been asked to determine if the additive is effective. They have 10 professional drivers and 10 six- passenger cars of the same make and model and 10 four- passenger cars of the same make and model.

(A) Design an experiment to test the effectiveness of the additive on both the six-passenger cars and the four-passenger cars.

(B) Explain what type of hypothesis test you would use to test the effectiveness of the additive. Write both the null and alternate hypotheses. Define any variables used.