Question 21 Pushing on a rock accomplishes no work unless there is O opposing force O movement O a net force O movement in the same direction as the direction of the forceQuestion 22 Which condition or conditions are necessary for rotational equilibrium? A. EFX = 0 B. EFX = 0; ET = O C. ET = 0 D. EFX = 0; EF = 0 OB OD OC OA