Compressible fluids. Throughout this chapter, we have dealt only with incompressible fluids. But under very high pressure, fluids do, in fact, compress. (a) Show that the continuity condition for compressible fluids is $\rho_{1} A_{1} v_{1}=\rho_{2} A_{2} v_{2}$
where $\rho$ is the density of the fluid. (b) Show that your result reduces to the familiar result for incompressible fluids.