The manager of a museum wants to conduct a survey to determine how people view their experience at the museum. which would give him the most representative sample for the survey?

conducting the survey as customers exit the museum

conducting the survey at one exhibit in the museum

conducting the survey at the museum cafeteria

conducting the survey at a shopping mall

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.