A diagnostic sonogram produces a picture of internal organs by passing ultrasound through the tissue. In one application, it is used to find the size, location, and shape of the prostate in preparation for surgery or other treatment. The speed of sound in the prostate is 1525 m/s, and a diagnostic sonogram uses ultrasound of frequency 2.75 MHz. The density of the prostate is 1060 kg/m3.

Question

A diagnostic sonogram produces a picture of internal organs by passing ultrasound through the tissue. In one application, it is used to find the size, location, and shape of the prostate in preparation for surgery or other treatment. The speed of sound in the prostate is 1525 m/s, and a diagnostic sonogram uses ultrasound of frequency 2.75 MHz. The density of the prostate is 1060 kg/m3. 
What is the wavelength 𝜆 of the sonogram ultrasound?
What is the bulk modulus 𝐵 for the prostate gland?

I don't want the answers I just want help with which equations to use here.

Damon · Accepted Answer

http://hyperphysics.phy-astr.gsu.edu/hbase/Sound/souspe2.html

Eric · Answer

I know that velocity = frequency x wavelength but I don't understand how the bulk modulus fits in here, how do I solve that?

Damon · Answer

and yes ,velocity ALSO = distance/time = wavelength/period = frequency*wavelength