Explanation:
Compute the average score for each subject across the years 2000-2003. For each subject, sum the four yearly scores and divide that sum by 4 to get the subject's mean over the four-year span.
Compare those four means; the subject with the largest average is the one in which students performed best on average.
Answer: The pigs are interacting socially with humans and adopting their behaviors.
Explanation:
