水泵的Q-H特性曲线如有上升段，那么水泵就存在不稳定工况点。_爱下问搜题

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问题判断题

水泵的Q-H特性曲线如有上升段，那么水泵就存在不稳定工况点。

答案

参考答案：对

选择题

下列物质中，不能提供人体活动所需能量的是（　　）

A．葡萄糖

B．油脂

C．酒精

D．食盐

单项选择题

Questions 14-23

·Look at the ten statements for this part.
·You will hear a passage about "the number of genes ". You will listen to it twice.
·Decide whether you think each statement is right(R), wrong(W) or not mentioned(NM).
·Markyour answers on the Answer Sheet.

The first detailed study of the human gene map claimed that humans have about thirty thousand genes.

A．Right

B．Wrong

C．Not Mentioned