A boundary layer is a thin region (usually along a wall) in which viscous forces are significant and within which the flow is rotational. Consider a boundary layer growing along a thin flat plate. The flow is steady. The boundary layer thickness delta at any downstream distance $x$ is a function of free-stream velocity $V$, and fluid properties $p$ (density) and $u$ (viscosity). Use the method of repeating variables to generate a dimensionless relationship for $d$ as a function of the other parameters.

Solution:
A. $Delta = f(Re)$
B. $Delta/x = f(Re)$
C. $Delta/x = f(Re+1)$
D. None of these