Respuesta :

Answer: frecuency =3Hz    ; period = 1/3(s)

Explanation: frecuency (f  measured in Hz)is the number of times (12times) the object vibrates in a given period of time(4s). In our case f=12/4 = 3Hz.

We use SI units

Period = 1/T = 1 / 3 = 0.333 Hz

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