quation $(7\mathrm{.}1$b$)$ assumes that the boundary layer on the plate is turbulent from the leading edge onward. Devise a scheme for determining the boundary layer thickness more accurately when the flow is laminar up to a point Re x$,$ crit and turbulent thereafter. Apply this scheme to computation of the boundary layer thickness at x $=1\mathrm{.}5$m in $40$m$/$s flow of air at $20$C and $1$ atm past a flat plate. Compare your result with Eq$.(7\mathrm{.}1$b$).$ Assume Re x$,$ crit $1\mathrm{.}2$E$6.$

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