where U$=3$ m$/$s is the free$-$stream velocity outside the boundary layer $($y$>$$)$ and the boundary layer thickness $($x$)$ varies in the streamwise x$-$direction $($depends on x$).$ The boundary layer thickness is measured at section a$-$b such that ab$=2$ mm and cd$=3$ mm at section c$-$d$.$ The fluid is water with density $=1000$ kg$/$m$3.$ The plate width perpendicular to the paper is w$=0\mathrm{.}2$ m$.$ Assume two$-$dimensional, steady state, and incompressible flow. The height of the control volume $($a$-$b and c$-$d$)$ is not specified and is at your discretion, as along as b and c are at the same height outside of the boundary layer.