在我国同级国家机构中，居于主导地位的是______ A．立法机关 B．行政机关 C

根据首字母或中文意思完成句子

1. He is so s____ that no one can persuade him.

2. Do you remember every ____ (细节) of the story you have just read?

3. Excuse me; what is the f____ to Paris? Is $l0 enough?

4. All these goods here will be ____ (运输) abroad by ship within 3 days.

5. He is a determined person. If he d____ to do something, he will do it well.

6. I am not ____ (熟悉)with the city, for this is my first visit here.

7. Finally, they succeeded in ____ (说服) her to cycle around China.

8. He was ____ (骑车) along the street when he was knocked off his bike.

9. His grandpa would sit there, looking at the ____ (流动) of traffic.

10. We should have the determination to correct our ____. (缺点)

it's cold here. You’d better __ your clothes.

A. not put on   B. take off   C to put on   D. not take off

如图所示，在磁感应强度大小B=0.5T的匀强磁场中，有一竖直放置的导体框架，框架宽l=0.4m，框架上端的电阻R=0.9Ω，磁场方向垂直于框架平面．阻值r=0.1Ω的导体棒ab沿框架向下以v=5m/s速度做匀速运动，不计框架电阻及摩擦．问：

（1）通过ab棒的电流是多大？方向如何？

（2）ab受到的安培力是多大？

（3）这个过程中能量是怎样转化的？

进行钢筋代换时，对抗裂要求的构件的螺纹钢筋，常用（）钢筋，以免裂缝开展过大。

产生热冲击的原因有哪些？