To illustrate the effects of driving under the influence? (DUI) of? alcohol, a police officer brought a DUI simulator to a local high school. Student reaction time in an emergency was measured with unimpaired vision and also while wearing a pair of special goggles to simulate the effects of alcohol on vision. For a random sample of nine? teenagers, the time?(in seconds) required to bring the vehicle to a stop from a speed of 60 miles per hour was recorded. How would I use a? 95% confidence interval to test if there is a difference in braking time with impaired vision and normal vision where the differences are computed as? "impaired minus? normal."?

Subject                   1          2         3         4         5         6        7       8         9     

Normal, Xi             4.49    4.34    4.58     4.65    4.31    4.80   4.59   5.00   4.79

Impaired, Yi          5.86    5.85     5.51    5.29    5.90    5.49   5.23    5.61   5.63