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What property is a characteristic of a substance that can be observed and does not change the identity of the substance

Awave travels at a speed of 5.2 m/s. if the distance between crests is 0.40 m, what is the frequency of the wave? use f=v/wavelength a. 13 hz b. 2.1 hz c. 0.077 hz d. 5.6 hz

Often called simply "velocity," this is the velocity of an object at a particular moment in time.