If a string vibrates at the fundamental frequency of 528 hz and also produces an overtone with a frequency of 1,056 hz, this overtone is the
*a. *second harmonic.
*b. *first harmonic.
*c. *fourth harmonic.
*d. *third harmonic.

14. the of a sound wave is defined as the amount of energy passing through a unit area of the wave front in a unit of time.
*a. *amplitude
*b. *compression
*c. *intensity
*d. *frequency