Wave length because your measuring the length of the wave I believe this is the correct anwser
mass is the weigh and force is a push or pull and motion is movements
may be wrong but worth a try
The correct answer is frequency
The Doppler effect is characterized by the change in the sound frequency emitted by a source, perceived by an observer when there is relative movement. A typical example of the Doppler effect is the case of an ambulance with the siren on, during the approach or removal of an observer.
A socialist who puts gender at the center of the analysis of the social world can be said to be using "<span>feminist theory".
Feminist theory is a noteworthy branch of theory inside sociology that is unmistakable for how its makers move their scientific focal point, presumptions, and topical concentration far from the male perspective and experience. In doing as such, Feminist theory sparkles light on social issues, patterns, and issues that are generally disregarded or misidentified by the truly overwhelming male point of view inside social theory.
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