题目内容
（请给出正确答案）
[主观题]
Which of the following statements is/are true regarding hydraulic pumps in general？ .
A.Variable volumes can be obtained with gear pumps only by variation of the pump drive speed
B.A radial piston pump houses sliding pistons in a stationary cylinder block through which passes a rotating pintle or ported shaft
C.The amount of fluid displaced per revolution of an axial piston rotary pump is dependent on the angle formed between the cylinder block and valve plate
D.All of the above
如搜索结果不匹配，请 联系老师 获取答案
