What are beats? a. periodic fluctuations in the velocity of sound waves b. periodic fluctuations in the wavelength of sound waves c. periodic fluctuations in the intensity of sound waves d. periodic fluctuations in the frequency of sound waves

D. periodic fluctuations in the frequency of sound waves

Explanation:

Beat is referred to the phenomena that occurs when to sound waves interfer with each other and they have different frequencies.

This difference is what creates a beating, wich in sound waves manifest as high and low sounds, this as a result of the oscilating frequency .

the cellphone, they would then know if the killer would have contacted them or always hated them. or if it was a breakup. but if that is not the case, then it would be the clothing. to put in a bullet, it would have to be put in by hands. hands have finger prints which, would have giving you the answer of who done it.

explanation:

you can cut your hand off if your not