1. Tire Design An engineer has just developed a new tire design. However, before going into production, the tire company wants to determine if the new tire reduces braking distance on a car traveling...

1. Tire Design An engineer has just developed a new tire design. However, before going into production, the tire company wants to determine if the new tire reduces braking distance on a car traveling 60 miles per hour compared with radial tires. Design an experiment to help the engineer determine if the new tire reduces braking distance.

2. Octane Does the level of octane in gasoline affect gas mileage? To answer this question, an automotive engineer obtains 60 cars. Twenty of the cars are considered to be compact, 20 are full size, and 20 are sport utility vehicles (SUVs). Design an experiment for the engineer. Include a diagram to illustrate your design.

3. School Psychology The school psychologist first presented in Problem 9 worries that girls and boys may react differently to the two methods of instruction. Design an experiment that will eliminate the variability due to gender on the response variable, the score on the achievement test. Include a diagram to illustrate your design.