在离心泵装置中,管路的特性曲线,同泵的特性曲线交点,称为()
A.工作点
B.设计点
C.稳定点
D.高效点
参考答案:A
词汇运用
1. I am really s_______ that he can pass math.
2. What language can he s________?
3. Can you t_______ me how to get to your house?
4. He is p________ basketball on the ground.
5. He is the c________ of the school soccer team.
6. The old man enjoys ________(居住) in the quiet place.
7. Do you want to ________(写) stories?
8. Some animals sleep ________(在……期间) winter.
9. Mr. Lee ________ (放松)at home on weekends.
10. If you are ________(饥饿), you can buy some food in the supermarket.
对嗜酸性粒细胞起正向趋化作用的物质是()。
A.肝素
B.组胺
C.慢反应物质
D.嗜酸性粒细胞趋化因子
E.血小板活化因子