A smooth, flat plate of length \(\ell=6 \mathrm{~m}\) and width \(b=4 \mathrm{~m}\) is placed in water with an upstream velocity of \(U=0.5 \mathrm{~m} / \mathrm{s}\). Determine the boundary layer thickness and the wall shear stress at the center and the trailing edge of the plate. Assume a laminar boundary layer.