Let y be the distance from the wall, ut be the shear velocity and be the kinematic viscosity. Which of these equations define y+?

Let y be the distance from the wall, ut be the shear velocity and be

1.	Let y be the distance from the wall, u_t be the shear velocity and be the kinematic viscosity. Which of these equations define y⁺?
A.	y<sup>+</sup>=y/u<sub>t</sub>
B.	y<sup>+</sup>=u<sub>t</sub> /y
C.	y<sup>+</sup>=(y u<sub>t</sub>)/
D.	y<sup>+</sup>=u<sub>t</sub>/y
Answer» D. y<sup>+</sup>=u<sub>t</sub>/y