Read the study and determine whether or not each description applies. Tyrel is testing whether exposure to political news causes people to be more opinionated. For each participant, Tyrel flips a coin and places all the heads in one group and all the tails in another. The heads group watches 20 minutes of political news, while the tails group watches 20 minutes of local nonpolitical news. Afterward, all participants write a persuasive essay and Tyrel measures how strongly and how many times they state their opinions.

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.