问题 单项选择题

恒功率液压泵的原理实际上是使泵的()。

A.每转排量保持恒定

B.每转排量随排压增高而降低

C.每转排量随排压增高而增高

D.排出压力保持恒定

答案

参考答案:B

问答题

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请回答:新中国在50年代是怎样以独立自主的姿态步入国际舞台的?70年代又取得了哪些外交上的新突破?                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                

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