给水排水制图中的沟渠和重立流管道宜标注()标高。
A、管中心
B、管内底
C、管顶
D、以上都可以
参考答案:B
根据汉语、首字母及句子意思补全句子。
1. Go________ (穿过) the street when the light is green.
2. I'm very ________ (饥饿的) . I want some food to eat.
3. How do you ________ (抵达) at the airport?
4. In the g________, there are some vegetables.
5. We saw her when she p________ the classroom.
能量转换型传感器,也称有源传感器。