Nielsen Monitor-Plus, a service of Nielsen Media Research, is one of the leaders in advertising information services in the United States, providing advertising activity for 16 media, including television tracking, in all 210 Designated Market Areas (DMAs). One of the issues it has researched is the increasing amount of "clutter" - nonprogramming minutes in an hour of prime time - including network and local commercials and advertisments for other shows. Recently it found the average nonprogramming minutes in an hour of prime-time broadcasting for network television was 15:48 minutes. For cable television, the average was 14:55 minutes.
a. Calculate the difference in the average clutter between network and cable television.
b. Suppose the standard deviation in the amount of clutter for both the network and cable television was either 5 minutes or 15 seconds. Which standard deviation would lead you to conclude that there was a major difference in the two clutter averages? Comment