Answer: Reaction is the ability of a wave to bounce back but not be absorbed. When a wave strikes a boundary,
it makes an abrupt change of direction, which depends upon the angle the wave strikes, but the speed of
the wave is not changed. One characteristic of waves is the law of reaction: the angle at which the wave approaches a at, reactive surface is equal to the angle
at which the wave leaves the surface.
Step-by-step explanation: