Reproducing eqs. 15, 18 and 19 from the typed notes on turbulence for this course, the reynolds-averaged navier-stokes (rans) equations for a constant- density turbulent flow which is steady and whose mean flow is two-dimensional may be written as consider applying these equations to a turbulent boundary layer. the mean flow continuity equation displayed here has the same form as for a laminar boundary layer. we may assume, as usual, that the boundary layer is thin, which means the mean streamwise velocity (u) varies mainly with distance y from the wall. in addition, for this flow the reynolds stress components u, id v2 are generally of the same order of magnitude (a) with the statements made above, show how eqs. 2 and 3 can be simplified for the case of a turbulent boundary layer on a flat plate, at zero angle of attack (b) explain, in your own words, and with appropriate sketches, why uv is expected to be of opposite sign to u, especially near the wall.