The statement that is NOT true about the difference between laminar and turbulent boundary layers is:1.the Reynolds number for a turbulent boundary layer is higher than that for a laminar boundary layer. 2.the wall shear stress for a turbulent boundary layer is greater than that for a laminar boundary layer. 3.a turbulent boundary layer is thicker than a laminar boundary layer.4.the velocity gradient at the wall is greater for a laminar boundary layer than a turbulent boundary layer.