Project C.I. for Small Samples

The Illinois State Racing Commission monitors horse racing at all the state racetracks and Summer county fairs.  In each race, the winning horses and a randomly selected horse are checked for performance enhancing drugs.  Blood and urine samples are collected by a veterinarian and sent to the state lab.  One test that is performed is a blood-gas analysis.  This test measures the amount of Carbon Dioxide (CO2) in the blood.  If the CO2 level is 37 millimoles or more per liter for a nonlasix horse or 39 millimoles per liter or higher for a lasix horse, the horse is in violation.  This can lead to the owner forfeiting his winnings, paying a fine and serving a suspension.

Given the tested horses in 3 races had blood samples with CO2 levels of 
Race 1
Horse 1 (Lasix): 39.2, 39.4, 39.0 and 39.1 millimoles per liter
Horse 2 (Nonlasix):  36.2, 36.5, 37.0, 36.0 millimoles per liter
Horse 3 (Lasix):  37.9, 38.0, 37.4, 38.1 millimoles per liter
Horse 4 (Nonlasix):  37.1, 37.2, 37.3, 37.4 millimoles per liter

Race 2
Horse 1 (Lasix): 39.2, 39.8, 39.6 and 39.1 millimoles per liter
Horse 2 (Nonlasix):  36.4, 37.8, 37.2, 36.3 millimoles per liter
Horse 3 (Lasix):  41.0, 39.2, 40.1, 39.1 millimoles per liter
Horse 4 (Nonlasix):  37.7, 37.5, 37.1, 37.2 millimoles per liter

Race 3
Horse 1 (Lasix): 39.8, 40.4, 38.0 and 39.7 millimoles per liter
Horse 2 (Nonlasix):  37.2, 37.5, 37.0, 36.4 millimoles per liter
Horse 3 (Lasix):  40.0, 39.6, 39.2, 40.1 millimoles per liter
Horse 4 (Nonlasix):  37.1, 37.2, 37.1, 37.0 millimoles per liter

A.  Find a 95% confidence levels for the CO2 level in each horse.

B.  Is any horse in violation (the entire interval is above the legal limit)?
     Note:  This is one of tests used used by the Illinois Racing Commission for
                harness and thoroughbred race horses.

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