单吸泵是叶轮一侧有液体吸入口的离心泵。
A. 对
B. 错
平衡鼓是个圆柱体，装在末级叶轮之后，随转子一起旋转。
A. 对
B. 错
While the four Ps help us remember the basics components of the ________, they don't have significant relevance in the marketing process.
A. production operation
B. marketing mix
C. product development process
D. competitive benchmarking process
Marketers define a ________ as any physical good, service, or idea that satisfies
A. product
B. copyright
C. prototype
D. concept
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