The scatter plot shows the relations between the test scores of a group of students and the number of hours they play computer games in a week: Part A: What is the group of points labeled A called? What is the point labeled B called? Give a possible reason for the presence of point B.

Part B: Describe the association between students' test scores and the number of hours they play computer games.

An automobile assembly line operation has a scheduled mean completion time, μ, of 12 minutes. the standard deviation of completion times is 1.6 minutes. it is claimed that, under new management, the mean completion time has decreased. to test this claim, a random sample of 33 completion times under new management was taken. the sample had a mean of 11.2 minutes. assume that the population is normally distributed. can we support, at the 0.05 level of significance, the claim that the mean completion time has decreased under new management? assume that the standard deviation of completion times has not changed.