3-38. The  following  statements  concern the operation of the counterbalance  valve  shown  in figure 6-20 of your textbook. Mark each statement true of false,    then select the alternative  below  that  lists those that are true. A.The  main  valve  has  equal surfaces  which  are  the  inner areas of the spool.    The activation of the valve B. results  from  the  applied pressure  opening  the  check valve,   allowing the fluid to bypass the main valve. C.   Reverse action of the valve   is controlled by the pressure  required  to overcome  the  spring  tension of a check valve. D.   The weight supported by the valve  depends  upon  the spring tension on the spool. 1. A, B, C 2. A, C, D 3. B, C, D 4. A, D Learning  Objective: Recognize construction  features,  operating characteristics,  and  uses  of various  types  of  directional control valves. 3-39. A poppet is used as the valving element for which of the following  fluid  power  valve applications? 1. Flow control 2. Pressure  control 3. Directional  control 4. All of the above 3-40. What type of valving element is most  commonly  used  in  directional control  applications? 3-41. Check  valves  usually  contain  what types of valving elements? 1. Ball and cone 2. Ball and poppet 3. Sleeve and poppet 4. Rotary  spool  and  sliding spool 3-42. What type of check valve permits free flow of fluid in one direction and a limited flow of fluid  in  the  opposite  direction? 1. Orifice 2. Vertical 3. Swing 4. Ball 3-43. Refer to figure 6-25 in your textbook. Force caused by which of the following plays no part in the opening and closing of this valve? 1. Gravity 2. Spring  action 3. Backflow  of  fluid 4. Forward flow of fluid 3-44. Refer to figure 6-27 in your textbook. If normal system inlet pressure is lost, when the alternate  system  is  activated, its pressure will cause the shuttle  to  move  sufficiently  to 1. close the outlet port to prevent reverse flow from the outlet port to the normal system inlet 2. close the outlet port and connect  the  normal  system inlet to the alternate system inlet 3. apply  the  alternate  system pressure to both the outlet port and the normal system 4. close the normal system inlet to prevent loss of alternate system  pressure 1. Ball 2. Poppet 3. Rotary spool 4. Sliding spool 20