A periodic von Karman vortex street is formed when a uniform stream flows over a circular cylinder. Use the method of repeating variables to generate a dimensionless relationship for von Karman vortex shedding frequency $f_k$ as a function of free-stream speed $V$, fluid density $p$, fluid viscosity $u$, cylinder diameter $D$, and speed of sound $c$.

Solution:
A. $St= f(Re(c))$
B. $St= Re(c)$
C. $St= f(Re(D))$
D. None of these