As an analogy to wave packets, consider an "automobile packet" that occurs near the scene of an accident on a freeway. The phase speed is analogous to the speed of individual automobiles as they move through the backup caused by the accident. The group speed can be identified as the speed of the leading edge of the packet of cars. For the automobile packet, which of the following is true? a. The group speed is greater than the phase speed. b. The group speed is the same as the phase speed c. The group speed is less than the phase speed