Which of the following conditions must be met for us to apply the most useful version of the Conservation of Momentum Equation (Equation 2.10N is an example for the x-direction) we derived in class? Select one . There must be steady state conditions, Cross out CROSS out O b. Any momentum flows into or out of the control volume (CV) must be perpendicular to the control surface; cross out OC. The momentum flows into or out of the control volume must act in the same direction as the forces acting on the control volume; Cross out d. All of the above are true; CROSS Out o e. Only (a) and (b) are true; CROSS Out None of the above are true