Consider an advertisement at the movies. before you can see the newly released movie you have just paid to see, you must sit through a variety of trivia slides, snack bar ads, paid product advertising, and movie trailers. although the total barrage of advertising may last up to 20 minutes or more, a particular theater chain claims that the average length of any one advertisement is no more than 3 minutes. to test this claim, 50 theater advertisements were randomly selected and found to have an average duration of 3 minutes 15 seconds with a standard deviation of 30 seconds. do the data provide sufficient evidence to indicate that the average duration of theater ads is more than that claimed by the theater?