I'm having some trouble on this problem. "The human ear is most sensitive to sounds at about f = 3 kHz. A very loud sound at that frequency would have a displacement amplitude of about 4um. What is the pressure amplitude? (Assume the wave to be sinusoidal. For air at room temperature, B = 1.42 x 10^5 Pa and p = 1.20 kg/m^3.) Compare this to the typical diurnal variation in atmospheric pressure, about 500 Pa = 0.005 atm."