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【单选题】
Hydraulically, servo－operated, automatic, change over valves, utilized in a two ram hydraulic steering gear, serve to .A.
allow an alternate main pump to start in the fully loaded condition thus developing immediate full torque
B.
prevent either main pump from being hydraulically motored when idle by cross pressure flow
C.
prevent both units from operating simultaneously which could result in doubling the flow of oil and pressure leading to over pressurization of the system
D.
all of the above
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皮皮学刷刷变学霸
举一反三
【单选题】关于颞下颌关节的障碍(s) 的描述错误的是
A.
颞下颌关节障碍通常与肌肉、关节或两者的损伤有关
B.
颞下颌关节障碍不包括咀嚼力的减弱与磨牙
C.
日常不当的嘴部运动习惯(如:磨牙，经常性的咬伤嘴和舌头)是s的影响因素之一
D.
长时间头部的前屈姿势可能会导致s
E.
s可能会发展成骨关节炎和严重的退行性改变
【单选题】Looking out of her window one day, she sees a family its way down the road and comes to the realization that she needs to begin to live in the moment.
A.
有一天,她从窗户望出去,看到一家人正沿着路向前走,她意识到她需要开始活在当下。
B.
有一天,她从窗户望出去,看到一家庭艰难地在走,她意识到她需要开始活在当下。
【单选题】The window is broken. So it needs _____. [ ]
A.
being repaired
B.
repairing
C.
repaired
D.
to be repairing
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