Answer: Alcohol often cause the eye to become less responsive.
Reliable is not one of the Three R's.
The procedure is a refraction or vision test. The doctor may use a computerized refractor or simply shine a light into your eyes.
Answer:
Probability of tractor do not start = 7.67%
Explanation:
Given data:
Probability of not start at red = 6%
Probability of not start at white = 11%
Probability of not start at Blue = 8%
Percentage of tractors produced in red line = 48%
Percentage of tractors produced in white line = 31%
hence Percentage of tractors produced in white line = 1 - 0.48 - 0.31 = 0.21
Probability of tractor do not start 
Probability of tractor do not start = 0.0288 + 0.0231 + 0.0248 = 0.0767
Probability of tractor do not start = 7.67%