List and define two characteristics of regular, periodic waveforms

Two characteristics of regular, periodic waveforms are : 

1)  Amplitude  -  It is the the length and width of waves, such as sound
                          waves, as they move or vibrate. An example would be how
                          much a radio wave moving back and forth.

2)  Frequency -  It is the number of waves cycles per unit of time, passing a
                          point per unit time. It is usually measured in Hertz.

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