(same data as previous problem) The manager of a soda bottli…

(same data as previous problem) The manager of a soda bottling plant is interested in comparing the performance of two bottling machines, the old machine and a new machine that has just been purchased. For each machine she selects 10 one-hour periods at random and records the number of crates completed in each hour. The table below gives the results. New 78 87 79 82 87 81 85 80 82 83 Old 74 77 78 70 87 83 76 78 81 76   (b)     Give a 90% confidence interval for the difference in the two means. (Don’t forget the sentence.)

Does the type of movie that children are watching make a dif…

Does the type of movie that children are watching make a difference in the amount of snacks they will eat?  Seventy-five randomly selected children were randomly assigned to watch either a cartoon, a science fiction, or a live action musical (25 to each). Cheese crackers were available in a bowl, and the investigators compared the number of crackers eaten by children while watching different kinds of movies. What are the response variable and the explantory variable in this study?