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單項(xiàng)選擇題

With reference to a rotary vane steering gear system, which one of the following statements is true?()

A.The three moving vanes and the three fixed vanes form three pressure chambers
B.The three moving vanes and the three fixed vanes form six pressure chambers
C.The three moving vanes and the three fixed vanes form nine pressure chambers
D.The three moving vanes and the three fixed vanes form twelve pressure chambers

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