Baxter Pharmaceuticals has developed a new drug, TPC, designed to maintain a certain viral blood cell count at 600 points plus or minus a few percents. In support of their application to distribute the drug nationally, Baxter submitted sample data to the Food and Drug Administration (FDA) on 125 of the 3,000 patients who used the drug on a trial basis. For the 125 patients tested, the average viral count was 560; however, the FDA withheld permission to distribute the drug because the 560 was 40 points below the 600 expected. To gain approval, Baxter decided to phone the attending physicians of all 3,000 patients who were using the drug on the trial basis. Upon receiving all these data they found that the average viral count was 596. Baxter summarized the results of the survey, sent the data to the FDA, and ultimately received their approval. What are the respective values of the parameter and statistic in this study? How would you explain the difference between the population value and the sample statistic—assuming the population value was correct and the sampling procedure was appropriate? Identify some possible sources of error.